Write the equation x+5y-2= 0 in normal form. Then, find the length of the normal and the length and the angle makes with the positive x-axis.

Answers

Answer 1

Final answer:

The normal form of x + 5y - 2 = 0 is (1/√26)x + (5/√26)y - (2/√26) = 0. The length of the normal is 1, and the angle it makes with the positive x-axis can be calculated using tan θ = 5, which gives the angle as tan-1(5).

Explanation:

To rewrite the equation x + 5y - 2 = 0 in normal form, we need to express it in the form Ax + By + C = 0, where A2 + B2 = 1. The equation is already in this form, but we must divide each term by the square root of (12 + 52) to satisfy the condition for A2 + B2. After the division, the normal form becomes (1/√26)x + (5/√26)y - (2/√26) = 0.

The length of the normal is the magnitude of the vector (A, B), which in this case, is 1 due to the normalization. To find the angle θ that the normal makes with the positive x-axis, we use the relationship tan θ = B/A. For our equation, tan θ = 5/1, so θ = tan-1(5).

The analytical method of vector addition involves identifying the x- and y-components of vectors and merging them to calculate the resultant vector's magnitude and direction.


Related Questions

The function y=3.75 + 1.5(x-1) can be used to determine cost in dollars for a taxi ride of x miles. What is the rate of change of the cost in dollars with respect to the number of miles?

Answers

Answer:

1.5 dollars/miles

Step-by-step explanation:

Given function [tex]y=3.75 + 1.5(x-1)[/tex] can be used to determine cost in dollars for a taxi ride of x miles.

Now we need to find about what is the rate of change of the cost in dollars with respect to the number of miles.

First we need to rewrite [tex]y=3.75 + 1.5(x-1)[/tex] in y=mx+b form

[tex]y=3.75 + 1.5(x-1)[/tex]

[tex]y=3.75 + 1.5x-1.5[/tex]

[tex]y=2.25 + 1.5x[/tex]

[tex]y=1.5x + 2.25[/tex]

comparing with y=mx+b, we get m=1.5

Hence rate of change of the cost in dollars with respect to the number of miles is 1.5.

Find the limit of the function by using direct substitution. limit as x approaches zero of quantity x squared minus two.

Answers

Answer:

[tex]\lim_{x \to 0}\ x^2 -2 = -2[/tex]

Step-by-step explanation:

We have the following limit

[tex]\lim_{x \to 0}\ x^2 -2[/tex]

To solve this limit using direct substitution to substitute the value that tends x into f(x) and simplify.

In this case x tends to zero, then we substitute x = 0 in the function and simplify

[tex]\lim_{x \to 0}\ x^2 -2= (0)^2 -2= -2[/tex]

Therefore

[tex]\lim_{x \to 0}\ x^2 -2 = -2[/tex]

When x approaches 0 then f(x) it tends to -2

Find the surface area of the regular hexagonal prism. Round your answer to the nearest hundredth.

Answers

Answer:

860.55 mm²

Step-by-step explanation:

The surface area of an hexagonal prism, also known as an octahedron, is given by the following formula (since we have the apothem):

S= 6*b*(a+h)

where b = is the side of the base, a is the apothem length, and h = the height

S = 6 * 8 * (4√3 + 11) = 48 * 17.92812 = 860.55 sq mm

Could have also have used another formula without the apothem:

S =3 * √3 * b² + 6 * b * h

S = 3 * √3 * 8² + 6 * 8 * 11 = 3√3 * 64 + 528 = 332.55  + 528 = 860.55 sq mm

I NEED HELP ASAP PLZZZZ LOOK AT THE PIC

Answers

Answer:

The red line is g(x)

Step-by-step explanation:

* To solve this problem you must to know some fact about

  transformation

- If the function f(x) translated horizontally to the left  

 by h units, then the new function g(x) = f(x + h)

- If the function f(x) translated vertically up  

 by k units, then the new function g(x) = f(x) + k

- If the function f(x) translated vertically down  

 by k units, then the new function g(x) = f(x) – k

- A vertical stretching is the stretching of the graph away from

 the x-axis

• if k > 1, the graph of y = k•f (x) is the graph of f (x) vertically

 stretched by multiplying each of its y-coordinates by k.

- A vertical compression is the squeezing of the graph toward

 the x-axis.

• if 0 < k < 1 (a fraction), the graph is f (x) vertically compressed

 by multiplying each of its y-coordinates by k.

• if k should be negative, the vertical stretch or compress is

 followed by a reflection across the x-axis.  

* Now lets solve the problem

- g(x) = -1/2f(x + 2)

# x + 2 ⇒ means the graph moved 2 units to the left

# -1/2 ⇒ means the graph has vertical compressed followed

 by a reflection across the x-axis, then multiply

 each y-coordinate by -1/2

- The graph of f(x) intersects x-axis at point (3 , 0)

∴ The point will be (1 , 0) on g(x)

- The graph of f(x) intersects y-axis at point (0 , -6)

∴ The point will be (-2 , 3) on g(x)

* Look to the graph

# The red line is g(x)

# The blue line is f(x)

- To check your answer

# The equation of f(x) is f(x) = 2x - 6

∵ g(x) = -1/2f(x + 2)

∴ g(x) = -1/2[2(x + 2) - 6] = -1/2[2x + 4 - 6] = -1/2[2x - 2] = -x + 1

* g(x) intersect x-axis at point (1 , 0) and y-axis at point (0 , 1)

A jacket is on sale for 70% of the original price. If the discount saves $45, what was the original price of the jacket? What is the sale price?

Answers

I believe it is $64.28
First you divide 45/7 to find out what 10% of 45 is since 70% is $45
45/7= 6.42, so now you multiply 6.42 by 3 to fin out what the 30% is
6.42(3)= $19.28
Now you add $19.28+45 to add the 30% and the 70%, which is $64.28

100 - 70% = 30

0.30 × p (p=45)

0.30 × 45 = 13.5

the sale price is $13.50

Answer #6 and tell the steps of how u did it

Answers

Answer:

3131x+1

Step-by-step explanation:

Make equation simple

5x times 5x times 5x times 5x times 5x +x+1

Solve

5 times 5 times 5 times 5 times 5 = 3125

x times x times x times x times x times x = 5x

3125+5x=3130x

Now you might be thinking you cant add x but here your can because it is just broken apart

now add x+1

3131x+1

A car travels in the direction of 135°. What is its compass heading?

Answers

SE ( South East) is the answer I believe

A car travels in the direction of 135° its compass heading is South and East.

We have given the direction of 135°.

North 315 West East ASE South Car travels in a direction of 315.

315 = 270'+ 45".

What is the measure of angle?

The degree measure of an angle is determined by the amount of rotation in degrees from the initial side to the terminal side.

The angle 315" lies between south and east. Making an angle of 45 towards south and east.

To learn more about the angle visit:

https://brainly.com/question/25770607

#SPJ2

Identify the following as exponential or linear and growth or decay

Answers

This would be linear growth because the y values are increasing, but not at an exponential rate.

you find a triangle that has an area of 10 sq ft. the height of the triangle is 10 feet. what is the length of the base of the triangle?​

Answers

Solution:

Given :

Area of triangle = 10 ft² Height of triangle = 10 ft

So, We have to find the Base of Triangle .

Area of triangle = 1/2*b×h, Where represents

B represent Base H represent Height

Step : Substitute those value in Formula;

Area of triangle = 1/2 × b × h

10 = 1/2 × b × 11

20 = 11 × b

b = 20/11

b = 1.81 ft

Therefore, Base of Triangle is 1.81 ft

Final answer:

To find the base of a triangle with an area of 10 sq ft and a height of 10 ft, use the formula 1/2 × base × height. By rearranging the formula and substituting the known values, the base is calculated to be 2 feet.

Explanation:

The question is asking to find the length of the base of a triangle when the area is 10 square feet and the height is 10 feet. The formula for the area of a triangle is 1/2 × base × height. In this case, we know the area (10 sq ft) and the height (10 ft), and we need to solve for the base.

Inserting the known values into the formula gives us:

Area = 1/2 × base × height
10 = 1/2 × base × 10

To solve for the base, we rearrange the formula:

base = 2 × Area / height
base = 2 × 10 / 10
base = 2 feet

Therefore, the length of the base of the triangle is 2 feet.

___ cosb =1/2 sin(a+b)+sin(a-b)?

Answers

Answer:

That would be sina.

Step-by-step explanation:

sin(a+b) = sinacosb + cosasinb

sin(a-b) = sinacosb -  cosasinb

Adding we get  sin(a+b) + sin(a-b) = 2sinaccosb

so sinacosb = 1/2sin(a+b) + sin(a-b)

Answer:

sina

Step-by-step explanation:

We have

          sin(a+b) = sina cosb + cosa sinb ---------------------eqn 1

           sin(a-b) = sina cosb - cosa sinb ---------------------eqn 2

eqn 1 + eqn 2

          sin(a+b) + sin(a-b) = sina cosb + cosa sinb + sina cosb - cosa sinb

          sin(a+b) + sin(a-b) = 2sina cosb

          [tex]sina\times cosb =\frac{1}{2}(sin(a+b) + sin(a-b))[/tex]

So answer is sina

This table shows the length, in inches, of several nails.
Length (in.)

1
2


1
8



3
8



5
16



5
16



5
16



1
2



5
16



3
16



1
8



Create a line plot to display this data.
To create a line plot, hover over each number on the number line. Then click and drag up to plot the data.

Answers

A construction of the line plot for the length, in inches, of several nails is shown in the image attached below.

In Mathematics and Statistics, a line plot is a type of graph that is used for the graphical representation of data set above a number line, while using crosses, dots, or any other mathematical symbol.

In this scenario and exercise, we would make use of an online graphing calculator (tool) to graphically represent the given length (in yards) of several nails on a line plot as shown in the image attached below;

Length        Frequency

1/2                     2

5/16                   4

1/8                     2

3/8                     1

3/16                    1

In conclusion, we can reasonably infer and logically deduce that the mode of the data set is equal to 5/16 because it has the highest frequency of 4.

Complete Question;

This table shows the length, in inches, of several nails.

Length (in) 1/2, 5/16, 1/8, 1/2, 3/8, 5/16, 5/16, 3/16, 5/16, 1/8.

Create a line plot to display this data. To create a line plot, hover over each number on the number line. Then click and drag up to plot the data.

simplify the expression for the length? A) x + 6 B)x – 6 C)x + 2 D)x – 2

Answers

Answer:

A on edge

Step-by-step explanation:

Answer:

A

Step-by-step explanation:

kate has 2/3 yards of fabric to make small flags each flag requires 1/6 yards of fabric how many flags cane kate make​

Answers

Answer:

THE ANSWER IS 7

Step-by-step explanation:

CAUSE UR MOM IS A TRASHIE                 i'm sorry i meant YO MAMA

Final answer:

Kate can make 4 small flags from 2/3 yards of fabric since each flag requires 1/6 yards of fabric.

Explanation:

Kate has 2/3 yards of fabric and each small flag requires 1/6 yards of fabric. To find out how many flags Kate can make, you divide the total amount of fabric by the amount needed for one flag:

2/3 yards \/ 1/6 yards = 4 flags.

Here's the step-by-step calculation:

First, recall that dividing by a fraction is the same as multiplying by its reciprocal. In this case, the reciprocal of 1/6 is 6/1.

So, multiply 2/3 by the reciprocal of 1/6:

2/3 × 6/1 = 12/3 = 4.

Thus, Kate can make 4 small flags from the fabric she has.

Simplify the expression 3x(x – 12x) + 3x2 – 2(x – 2)2. Which statements are true about the process and simplified product?

Answers

Final answer:

Simplifying the expression requires expanding the brackets, combining like terms, and applying algebraic rules including distribution. The resulting simplified form is – 35x2 + 8x – 8 after properly eliminating unnecessary terms and ensuring the solution is valid.

Explanation:

To simplify the expression 3x(x – 12x) + 3x2 – 2(x – 2)2, we need to apply standard algebraic techniques such as distribution, combining like terms, and simplifying polynomial expressions.

Firstly, distribute the 3x across the parentheses: 3x×(x – 12x) becomes 3x2 – 36x2.

Then, expand the square: – 2(x – 2)2 becomes – 2(x2 – 4x + 4).

Next, we can simplify the expression by combining like terms and further distributing where necessary:

3x2 – 36x2 + 3x2 – 2x2 + 8x – 8

Combine like terms:

– 35x2 + 8x – 8

Eliminate terms wherever possible and check to see if the simplified expression is reasonable. We are using multiplication, distribution, and combination of like terms to simplify the algebraic expression.

Write the phrase "twelve more than the product of seventeen and a number" as a mathematical expression.
A. 12 – 17x
B. 12 + 17x
C. 12 > 17x
D. 17 + 12x

Answers

Answer:

The answer is B. 12+17x

Step-by-step explanation:

Twelve more stands for +12 and the product of seventeen and a number is equal to 17*x or 17x.

Answer: OPTION B.

Step-by-step explanation:

You need to remember that a product is the result of a multiplication.

Let be the number mentioned in the problem "x", "the product of seventeen and a number" means that:

[tex](17)(x)=17x[/tex]

 Now "twelve more than the product of seventeen and a number" indicates that you need to add 12 to [tex]17x[/tex].

Therefore, you can write the phrase in the following mathematical expression:

[tex]17x+12[/tex] or  [tex]12+17x[/tex]

This matches with the option B.

(17 points)
Determine if line AB is tangent to the circle

Answers

1. If AB is tangent to the circle, then

[tex]18^2=(2\cdot7.2)^2+10.8^2[/tex]

We have

[tex]18^2=324[/tex]

[tex](2\cdot7.2)^2+10.8^2=324[/tex]

so AB is indeed tangent to the circle.

2. The unlabeled leg is another radius of the circle so it has length 8. Then if AB is tangent to the circle,

[tex](10+8)^2=8^2+15^2[/tex]

but we have

[tex](10+8)^2=324[/tex]

[tex]8^2+15^2=289[/tex]

so that cannot be a right triangle and AB is not tangent to the circle.

Which statistical question could the data below answer ? Cost of toys

Answers

The statistical question that could be answered by the data is "maximum cost of toys".

The graph shown is a line graph which is a type of chart that displays data points connected by a line. It's a common way to visualize how a particular quantity changes over time or across different categories.

Line graphs makes it easy to determine statistical measures including minimum and maximum values of a category or data.

Here, the maximum cost of toys is 10 and the minimum is 5.

Which of the following is an outlier in the set of data below? I think it’s 12 but I’m not so sure.

Answers

I think the answer might be 2

because

in the data given above all the numbers are between 12-19 they are all bigger than 10

and then there's 2 which is very far from 12 or any other numbers there and it is also less than 10

which makes more sense for it to be an outlier.

Hope this helps

suppose that F(x)=x^3 and G(x)=-2x^3

Answers

Answer:

A

Step-by-step explanation:

Given a function f(x) = x^2, we can say:

g(x) = -(x^2) is the reflection of f(x) in the x-axish(x) = ax^2 is a vertical stretch if a > 1 and a vertical compression if 0 < a < 1

The negative sign in front says that G(x) is flipped over the x-axis with respect to F(x). Also, the 2 in front tells us that it is a vertical stretch of the function F(x), since a > 1.

Hence, answer choice A is right.

Answer:

it is answer A

Step-by-step explanation:

Ap*x

Find the perimeter of each figure in questions. use 3.14 pi​

Answers

Answer: 10.5

Step-by-step explanation:Find the perimeter of the figure. Use 3.14 for the pie and round your answer to one decimal.

This looks like a square with a line going from the right corner slanted down to the bottom left, but there is a half circle there so it doesnt actually touch the bottom left. on the right half of the line is 13 in.

x^2+y^2-16x-161=0 factor it

Answers

(x-8)^2+y^2=225 I'm not able to factor it

what is the value of the expression below 3 1/4 - 1 78​

Answers

Answer:1 3/8

Step-by-step explanation:

3 1/4 = 3 2/8

1 7/8 =1 7/8

3 2/8 = 2 10/8

1 7/8 = 1 7/8

2 10/8-1 7/8 =1 3/8

Answer: =1 [tex]\frac{3}{8}[/tex]

Step-by-step explanation:

First, Rewriting our equation with parts separated:

=3 + 1/4 − 1 − 7/8

Then, Solving the whole number parts:

3 − 1= 2

After, Solving the fraction parts

1/4−7/8=?

Find the LCD of 1/4 and 7/8 and rewrite to solve with the equivalent fractions.

LCD = 8

2/8−7/8=−5/8

Then, Combining the whole and fraction parts

2 − 5/8=1 3/8

Next, converting mixed numbers to fractions, our initial equation becomes,

134−158

Finally, doing all the work you answer is going to be :

=1/38* Hopefully this helps:)

Mark me the brainliest:)!!

∞ 234483279c20∞

Type the correct answer in the box. Round your answer to the nearest hundredth.
Scarlett is trying to find the height of a dam. She stands 90 meters away from the dam and records the angle of elevation to the top of the dam to be 26º.
Scarlett's height is 1.65 meters, so the height of the dam is meters.

Answers

Answer:

top question is not correct

Step-by-step explanation:

Answer:

what

Step-by-step explanation:


The volume of a cube is 85.184 cubic inches. What is the length of each side of the cube?

Answers

Answer:

4.4 inches

Step-by-step explanation:

To work out the length of each side of the cube you would need to cube root of the volume as seen below:

[tex] \sqrt[3]{85.184} [/tex]

And this gives the answer 4.4 inches.

Answer:

Volume = Length * Width * Height

A cube has equal length, width, and height values.

[tex]\sqrt[3]{85.184}[/tex] is 4.4

So the length of each side is 4.4 units

Jasmine wants to make a path from one corner of her yard to the other as shown. The path will be 3 feet wide. What is the area of the path?

Answers

Answer:

The answer is 90.

Step-by-step explanation:

Area of the path will be 90 square feet.

How to find the area of the path?The yard is rectangular in shape.In the figure, there are two right angles triangles on two sides of the pathArea of the path = (Area of the rectangular yard) - (Area of two right angled triangles)The width of the path is 3 feet.  So, the base of the right angled triangle = (12-3) feet = 9 feet Area of the right angled triangle =  base x height/2

= (9 x 30/2) square feet = 135 square feet

Area of the yard = ( length x breadth)

= ( 30 x 12) square feet = 360 square feet

Area of the part = {360 - 2(135)} square feet

                                  = 90 square feet

Area of the path will be 90 square feet.

You will get more details on: https://brainly.com/question/10585064

#SPJ2

answer this fast
will mark brainlist for sure
answer the question whichever u know
:)

Answers

Answer:

[tex]\large\boxed{1.\ 38\ and\ 22}\\\boxed{1'.\ 42\ and\ 30}[/tex]

Step-by-step explanation:

[tex]1.\\x,\ y-the\ numbers\ (x>y)\\\\\text{We have the system of equations:}\\\\\underline{\left\{\begin{array}{ccc}x-y=16\\x+y=60\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad2x=76\qquad\text{divide both sides by 2}\\.\qquad\boxed{x=38}\\\\\text{Put the value of x to the second equation.}\\\\38+y=60\qquad\text{subtract 38 from both sides}\\\boxed{y=22}[/tex]

[tex]1'.\\x-larger\ part\\x-12-smaller\ page\\\\x+(x-12)=72\\x+x-12=72\qquad\text{add 12 to both sides}\\2x=84\qquad\text{divide both sides by 2}\\\boxed{x=42}\\\boxed{x-12=30}[/tex]

Which statement about these rectangles is true ?

Answers

the answer for this question is the dilation is reduction

Answer:

The statement which is true about these rectangles is:

          The dilation is an enlargement.

Step-by-step explanation:

Dilation Transformation--

It is the translation which changes the size of the original figure.The shape of the figure is conserved.Also, in dilation either the size increases (i.e. the figure enlarges) or it decreases( i.e. the figure reduces).Also, in a polygon if there is a dilation then there is a scalar multiplication in each of the sides of the polygon.If the scalar multiple is greater than 1 then there is a enlargement.and if the scalar multiple is less than 1 but greater than 0 then there is a reduction.

Here we see that each of the sides of the original figure is multiplied by "1.5" to obtain a larger rectangle.

This means that the dilation is a enlargement.

( since the scalar is strictly greater than one )

Please expla your answer as well. THX!!!

Answers

Answer:

[-7,5]

Step-by-step explanation:

The range is all the permitted values of y in the function. The lowest to the highest.

Looking at the function, the lowest y value is -7

and

the highest y value is 5

So we can say the range is [-7,5], the last choice

An electronics company can spend no more than $4,000 on raw materials for circuit boards. The raw materials cost $10 per ounce for copper and $20 per ounce for silver.

To summarize the situation, a worker writes the inequality:

10c + 20s ≤ 4,000, where c is the number of ounces of copper material and s is the number of ounces of silver material.

Which graph's shaded region shows the possible combinations of raw materials the company can buy?

Answers

Answer:

Option B is the correct answer.

Step-by-step explanation:

In a symphony orchestra, there are 2 vacancies for cellists only, 4 vacancies for violinists only and 4 vacancies for any of these musicians. In how many ways can these vacancies be filled from 15 applicants, of whom 7 are violinists and 8 are cellists?

Answers

Answer:

123480

Step-by-step explanation:

We have to choose:

2 cellists from 8 cellists;4 violonists from 7 violonists;4 cellists or violonists from 9 remaining musicians (8-2=6 - cellists left, 7-4=3 - violonists left, 6+3=9 - left musicians in total)

1. 2 cellists from 8 can be chosen in

[tex]C_8^2=\dfrac{8!}{2!(8-2)!}=\dfrac{8!}{2!6!}=\dfrac{6!\cdot 7\cdot 8}{2\cdot 6!}=28[/tex]

different ways.

2. 4 violonists from 7 can be chosen in

[tex]C_7^4=\dfrac{7!}{4!(7-4)!}=\dfrac{7!}{4!3!}=\dfrac{4!\cdot 5\cdot 6\cdot 7}{4!\cdot 2\cdot 3}=35[/tex]

different ways.

3. 4 musicians from 9 can be chosen in

[tex]C_9^4=\dfrac{9!}{4!(9-4)!}=\dfrac{9!}{4!5!}=\dfrac{5!\cdot 6\cdot 7\cdot 8\cdot 9}{5!\cdot 2\cdot 3\cdot 4}=126[/tex]

different ways.

In total, there are [tex]28\cdot 35\cdot 126=123480[/tex] differnt ways to fill all vacancies.

Other Questions
Hello! So I was wondering for French, why do we use the feminine and masculine pronouns and nouns? Aren't they just the same thing? I need help with this question on USA Test Prep Plz help me with this what major problem in the coal mining industry did Thomas Newcomen's steam engine help solve? 8 * 4.9999a(345.5 x .98)^9 Which of these are likely to occur as the result of a sedentary lifestyle? select two correct answers.A low cardiorespiratory enduranceB healthy BMIC Good GradesD poor body composition In triangle XYZ, angle Z is a right angle. If sinX = 3/4, find tan Y. Someone plz explain! Both circles have the same center. The circumference of the inner circle is 77.872 centimeters. What is the area of the shaded region? which of the following best describe how science is different from other activities involving What is the value of x in the equation -x =4 -3x +6?A. 5B. 10C. -5D. -10Worth 10 points two times a number plus 8 is the same as 20 minus the number which of the following best describes how culture can influence consumer behavior? A. The beliefs transmitted by culture ensure that consumers make only rational choices B. Strong culture traditions make people more likely to react to peer pressureC. Cultures have traditions that involve consuming specific goods or servicesD. Personal preference are solely determined by culture and tradition The Answer id C! Cesium is a radioactive element which was released into the ocean after the Fuushima nuclear power plant meltdown in 2011. Cesium's half-life is 30 years, which means that for every unit of cesium, half of it will decay over 30 years. How does this affect the human populations that eat fish from this area?A.) Cesium's half-life is relatively long, so biomagnification could become a concern.B.) All of the cesium will decay in approximately thirty years; therefore, humans can just avoid eating the contaminated fish for thirty years.C.) Cesium levels will be acceptable in a short time, so biomagnification is not a concern and humans can eat fish as normal.D.) Cesium will only decay by half in fifteen years, so human populations should avoid eating fish in this area and avoid contamination How would i rewrite this equation so it is not in fraction form-5/(1-cos(-x)) 1. Drag and drop an answer to each box to correctly complete the derivation of a formula for the area of a sector of a circle.2. Drag and drop an answer to each box to correctly explain the derivation of the formula for the volume of a pyramid.3. The equation for a circle is x28x+y22y8=0 . What is the equation of the circle in standard form? so i graduated today thanks brainley :::D When you overfill your glass with water and theres a slight bulge at the top of the glass, you are witnessing the _____ property of water. Adhesive, cohesive, expansive. Which expression has a value of 36? A. 9/12 x 48 B. 6/7 x 21C. 10/13 x 39D. 3/7 x 42 zeros are always considered significant digits when they are to the left of the decimal point