NEED HELP PLS!!!!!!!!!!!! BRANLIEST+15 POINTS!
A rectangle has a width that is 3 less than twice the length. If the rectangle has an area of 170 square inches, what is the length of the rectangle?

Answers

Answer 1

Answer:

L = 10, w = 17

Step-by-step explanation:

Area of a rectangle is A = Lw.  We are told that the width is 3 less than twice the length, so we will change the width into some expression in terms of the length.

w = 2L - 3 and

length = L.

Filling in the area formula now, knowing that the area is given as 170:

170 = (2L - 3)(L) so

[tex]170=2L^2-3L[/tex]

Get everything on one side of the equals sign and throw it into the quadratic formula to factor it and solve for the values of L.  When we do this we get that L = 10 and L = -8.5

Since the 2 things in math that will NEVER EVER be negative are time and distance/length measures, it is safe to disregard the -8.5.  Therefore,

if L = 10, then

w = 2(10) - 3 and

w = 17


Related Questions

11cm long a ribbon is 24 cm long and a large paper clip is 5 cm long how much longer is the ribbon than string

Answers

Answer:

There's no string in your question so zero. If you find out how long the string is just subtract it from the ribbon

Step-by-step explanation:

American cars maker produce 5650000 cars each year in Europe that Americans make 6 million 550 cars the mistake did Ben make how can he fix it

Answers

Answer:

Ben has mixed up the digit for millions and hundred thousands: he wrote 5 in the place for millions and 6 in the place for hundred thousands, but it should be the other way. I think that he should exchange those two digits in the faulty report.

Craig stops at a gas station to fill his tank. He must choose between full-service and self-service and between regular, mid grade and premium gasoline. How many possible combinations are there?

Answers

Answer:

  6

Step-by-step explanation:

There are 2 service choices and 3 grade choices for each, a total of 2×3 = 6 choices.

What are the domain and range of the exponential function below?

[tex]F(x) = 5^x+6[/tex]

Answers

Answer:

B

Step-by-step explanation:

The domain is the set of x values for which the function is defined.

The range is the set of y values for which the function is defined.

Attached is the graph of the exponential function.

It is the basic graph of exponential function of y = 5^x which is shifted 6 units above (because of +6 at the end).

Looking at the graph, the domain is the set of all x values.

The range is anything above 6.

Correct answer is B.

Answer: b

Step-by-step explanation:

A P E X

You and your brother are reading the same novel. You want to get ahead of him in the book, so you decide to read 30 minutes longer than your brother reads. Write an equation for the number of minutes you read, y, when your brother reads x number of minutes. How many minutes will you read if your brother reads for 15minutes?

Answers

the equation would be y = 30 + x and if your brother will read for 15 minutes then you'll read for 45 minutes i believe.

The equation for the number of minutes you read, y, when your brother reads x number of minutes is y = x + 30. Therefore, if your brother reads for 15 minutes, you will read for 45 minutes.

To write an equation for the number of minutes you read, y, when your brother reads x number of minutes and you decide to read 30 minutes longer than him, you can represent this relationship as y = x + 30. This equation signifies that your reading time (y) is equal to your brother's reading time (x) plus an additional 30 minutes.

If your brother reads for 15 minutes (x=15), you can determine how many minutes you will read by substituting 15 into the equation for x, obtaining y = 15 + 30 = 45 minutes. Therefore, if your brother reads for 15 minutes, you will read for 45 minutes to stay ahead.

PLEASE HELP ASAP!!! CORRECT ANSWER ONLY PLEASE!!!

A spinner is divided into 4 sections. The spinner is spun 100 times.

The probability distribution shows the results.

What is P(2 ≤ x ≤ 4) ?

Enter your answer, as a decimal, in the box.

Answers

Answer:  0.80

Step-by-step explanation:

P (2 ≤ x ≤ 4) is: P(X = 2) + P(X = 3) + P(X = 4)

                   =     0.36    +    0.12    +     0.32

                   =             0.48             +     0.32

                   =                            0.80

It can also be calculated as: 1 - P(X = 1)

                                           =  1 -  0.20

                                           =     0.80

1) Which method is most efficient method to use to solve 2x^2+4x-3=0

2) Which method is most efficient method to use to solve x^2+5x-6=0

3) Which method is most efficient method to use to solve 2x^2+4x-7=0

A. Factoring
B. Isolating the x^2 term and finding the square root of both sides
C. Using the quadratic formula
D. All three methods would be

(The answer choices are the same for all the problems)

Answers

Answer:

1. C

2. A

3. C

Step-by-step explanation:

1. The equation is most easily solved through the quadratic formula since it’s a term is greater than 1.

2. The equation is most easily factored since it’s a term is 1.

3. The equation is most easily solved by the quadratic formula since it’s a term is greater than 1.

August hosted two dinner parties for his friends. Twenty guests attended the first party, and thirty-three guests attended the second party. What is the percentage increase of the number of guests from the first party to the second party?

Answers

Answer:

50%

Step-by-step explanation:

PLEASE ANSWER
A farmer is trying to determine the number of plantain plants in a farm that covers 24 acres. He marks off three acre plots at randomly selected locations in the farm. The first plot contains 291 plants, the second plot contains 327 plants, and the third plot contains 286 plants.


Part A: Using this data, determine which of the following quantities represent an estimate of the number of plantain plants in the entire farm.


A 151

B 301

C 3,616

D 7,232


Part B: Suppose that a plantain plant bears a single bunch on a single stem. An average bunch will have 8 hands of 15 plantains. The farmer determines that around 85% of the total acreage is ready to harvest and sell. If the value at farm level is around $140.00 per thousand of fruits units for plantain, determine the total value at farm level for this farmer after harvesting and selling all the plantains in his farm.


The total value is ____________.

Answers

Answer:

C

Step-by-step explanation:

Answer:

option c is the answer

hope it helps

and ur welcm

Ten times the sum of four and three

Answers

the answer is

10 × (4+3) = 70

Find the exact value of the following expression (without using a calculator): tan(Sin^-1 x/2)

Answers

Answer:

tan(Sin^-1 x/2)=  [tex]\frac{x/2}{\sqrt{1-x^{2}/4 } }[/tex]

Step-by-step explanation:

Let sin^-1 x/2= θ

then sinθ= x/2

on the basis of unit circle, we have a triangle with hypotenuse of length 1,   one side of length x/2 and opposite angle of θ.

          tan(Sin^-1 x/2) = tanθ

           tanθ= sinθ/cosθ

as per trigonometric identities cosθ= √(1-sin^2θ)

           tanθ= sinθ/ √(1-sin^2θ)

substituting the value sinθ=x/2 in the above equation

             tanθ= [tex]\frac{x/2}{\sqrt{1-x^{2}/4 } }[/tex]

now substituting the value sin^-1 x/2= θ in above equation

             tan(sin^-1 x/2) =  [tex]\frac{x/2}{\sqrt{1-x^{2}/4 } }[/tex]

!

90 POINTS WILL GIVE BRAINLIEST for which value of theta is cot theta equal to cos theta
The answer is 2pi but how so?

Answers

Answer:

...so cos t = cot t can only happen when cos t is 0 or sin t is 1. (But sin t = 1 only happens when cos t = 0, so cos t = 0 is enough.)  

arccos(0) is pi/2, plus or minus any multiple of pi.

Step-by-step explanation:

 

cotθ = cosθ  

cosθ/sinθ = cosθ  

sinθ = 1  

θ = π/2

pi also = to 3.14 etc.

Answer:

Step-by-step explanation:

[tex]cot \theta = cos \theta\\ \frac {cos \theta}{sin \theta} = cos \theta[/tex]

An easy solution is if [tex]cos \theta = 0[/tex], or [tex]\theta = \frac \pi 2[/tex], plus or minus any number of half circles.

i need help asapppppppp

Answers

Answer:

a) h(x)

b) q(x)

c) w(x)

Step-by-step explanation:

Finding the answers for this is easy.  Take two values for x that shows a different Y-value for each function on the graph and place them in the equations suggested to see which equation match their Y-value on the graph.

Let's take x = -1 and x = 1.

a) h(x) = | -x + 3 |

| - (-1) + 3| = | 4 | = 4

| - 1 + 3 | = | 2 | = 2

h(x) passes through (-1,4) and (1,2)

b)  q(x) = | x | + 3

|-1| + 3 = 4

| 1 | + 3 = 4

q(x) passes through (-1,4) and (1,4)

c) w(x)  = | x+ 3 |

| -1 + 3 | = | 2 | = 2

| 1 + 3 | = | 4 | = 4

w(x) passes through (-1,2) and (1,4)

Two hikers are walking along the Appalachian Trail. The first hiker is 2 miles ahead of the second hiker. Both hikers are traveling in the same direction at the same speed, 1 mile per hour. Let x represent the distance traveled by the first hiker after a certain time period.


Several students wrote equations for this situation. Which student is correct?


A.

Alex said, “The equation y = 2x + 1 represents the total distance traveled by both hikers.”



B.

Brenda said, “The equation y = 3x represents the total distance traveled by both hikers.”



C.

Chris said, “The equation y = x – 2 represents the distance traveled by the second hiker.”



D.

Drake said, “The equation y = x + 2 represents the distance traveled by the second hiker.”


Answers

Answer:

Chris is correct. (Choice letter C)

Step-by-step explanation:

We can eliminate choices A and B from the get-go because the problem stated that both hikers are traveling at 1mi/hr. This means that the slope of the equation would equate to 1, so just x.

That leaves us with C and D. The two equations both have a slope of 1, but C has a y-intercept of -2 and D has a y-intercept of 2, which represents the starting location of the second hiker. The first hiker is the one who is ahead by 2 miles, so it can't be D. This leaves us with choice C. Chris is correct.

Answer:

C. Chris said, “The equation y = x – 2 represents the distance traveled by the second hiker.”

Step-by-step explanation:

find the angle between vector u=i+sqrt 7 j and vector v=-i-4j to the nearest degree.

a. 173 degrees
b. 145 degrees
c. 115 degrees
d. 97 degrees

Answers

hence angle between vectors is option a ,173 degree

What is Vector Equation?

When an equation has both direction as well as magnitude it refers to vector equation.

How to calculate angle between two vectors?

Formula used [tex]\alpha =cos^{-1} (\frac{u.v}{|u||v|})[/tex]

u.v=1*(-1)+[tex]\sqrt{7} *(-4)[/tex]

|u|=[tex]\sqrt{ 1^{2} +\sqrt{7} ^{2}}[/tex]=[tex]2\sqrt{2}[/tex]

|v|=[tex]\sqrt{ (-1^{2}) +(-4^{2})[/tex]=[tex]\sqrt{17}[/tex]

[tex]\alpha =cos^{-1} (\frac{-1-4\sqrt{7} }{|2\sqrt{2} ||\sqrt{17} |})[/tex]

[tex]\alpha =cos^{-1} (\frac{-1-10.58}{2.82*4.12})[/tex]

[tex]\alpha =cos^{-1} (\frac{-11.58}{11.61})[/tex]

[tex]\alpha =cos^{-1} (-0.99)[/tex]

hence option a 173 degree is correct

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What is the difference between an observational study and an​ experiment? Choose the correct answer below. A. In an​ experiment, a treatment is applied to an entire population and responses are observed. In an observational​ study, a researcher measures characteristics of interest of an entire population but does not change existing conditions. B. In an​ experiment, a researcher measures characteristics of interest of a part of a population but does not change existing conditions. In an observational​ study, a treatment is applied to part of a population and responses are observed. C. In an​ experiment, a researcher measures characteristics of interest of an entire population but does not change existing conditions. In an observational​ study, a treatment is applied to an entire population and responses are observed. D. In an​ experiment, a treatment is applied to part of a population and responses are observed. In an observational​ study, a researcher measures characteristics of interest of a part of a population but does not change existing conditions.

Answers

Answer: “A”

Step-by-step explanation: Your Answer Would Be “A”

Answer:

A

Step-by-step explanation:

THAT IS THE BEST ANWSER OPTION

Please please help me out please

Answers

Answer:

CD = 9.2 cm

Step-by-step explanation:

The arc of any circle is calculated as

arc = circumference × fraction of circle

     = 2πr × [tex]\frac{66.4}{360}[/tex]

     = 2π × 7.9 × [tex]\frac{66.4}{360}[/tex]

     = [tex]\frac{2(7.9)(66.4)\pi }{360}[/tex] ≈ 9.2

arc CD is approximately 9.2 cm

Math Post Q3 What inequality describes the graph?

Answers

For this case it is observed that the border of the region is not dotted, then the inequality includes an equal.

Thus, we discard options C and D.

We substitute the point (0,0) and see if it is fulfilled:

[tex]y\geq\frac {3} {2} x-3\\0 \geq\frac {3} {2} (0) -3\\0 \geq0-3\\0 \geq-3[/tex]

It is fulfilled, so the correct option is A.

Answer:

Option A

Answer:

A. [tex]y\geq \frac{3}{2} x-3[/tex]

Step-by-step explanation:

We are given a graph and we are to determine which inequality is described by the graph.

Since the graph has a solid line that means that the inequality includes the points on the line and must contain an equal sign.

So we will substitute the point (0, 0) to find the correct inequality.

[tex]y\geq \frac{3}{2} x-3[/tex]

[tex]0\geq \frac{3}{2} (0)-3[/tex]

[tex]0\geq 3[/tex] - true

[tex]y\leq \frac{3}{2} x-3[/tex]

[tex]0\leq \frac{3}{2} (0)-3[/tex]

[tex]0\leq 3[/tex] - false

Therefore, the correct inequality is [tex]y\geq \frac{3}{2} x-3[/tex].

the sum of two numbers is 61 and the difference is 19. what are the numbers?

Larger number:
Smaller number:

Answers

Answer:

the solution is (40, 21)

Step-by-step explanation:

Let the two numbers be x and y.

Then x + y = the sum = 61, and

         x - y = the difference = 19.

Solve the system of linear equations

x + y = 61

x - y  = 19

Combining these two equations:

x + y = 61

x - y  = 19

---------------

2x    =  80, so x must be 40.

Substituting 40 for x in the first equation, we get 40 + y = 61.  

Combining the constants, we get y = 21.

Then the solution is (40, 21).

The numbers whose sum is 61 and difference 19 are 40 and 21. This is obtained by using algebraic expression for the given condition.

Find the algebraic expression for the question:

Given that sum of numbers is 61 and difference is 19.

Let the larger number be x and smaller number be y.

Then we can write that, x+y=61 (sum) and x-y=19 (difference)

Calculate the numbers:

By solving the algebraic equations we can find the numbers.

From second equation we can write, x = 19+y Substitute this in first equation,

(19+y) + y = 61

19+2y = 61

2y = 61 - 19 = 42

y=42/2=21 ⇒ y=21 is the smaller number

x = 19+y = 19+21 =40 ⇒ x=40 is the larger number

Hence the numbers whose sum is 61 and difference 19 are 40 and 21.

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Maurice bought 3 sodas and 4 candy bars for $10.17. Larry bought 2 sodas and 5 candy bars for $10.28. How much does a candy bar cost?

Answers

Answer:

The cost of a candy bar is [tex]\$1.5[/tex]

Step-by-step explanation:

Let

x----> the cost of a soda

y----> the cost of a candy bar

we know that

[tex]3x+4y=10.17[/tex]-----> equation A

[tex]2x+5y=10.28[/tex]-----> equation B

Solve the system of equations by graphing

Remember that the solution of the system of equations is the intersection point both graphs

The solution is the point [tex](1.39,1.5)[/tex]

see the attached figure

therefore

The cost of a soda is [tex]\$1.39[/tex]

The cost of a candy bar is [tex]\$1.5[/tex]

There are 139 students and 10 adults on a field trip to the museum. The museum conducts tours in groups of 8. How many groups are needed for everyone to go on the tour.

Answers

Answer:

Step-by-step explanation:

139 +10 = 149

149 / 8 = 18.625

round  to nearest hundredth = 18

Please show all of your work! I will mark the brainliest nd gve thanks!
1.Find the standard equation of a circle with its center at (2, 8) and a radius of 10.
2. Find the standard equation of a parabola with its vertex at (2, 2) and a focus at (2, 5).
3. Find the standard equation of a parabola with its vertex at (5, 2) and a directrix x =3.

Answers

Answer:

Step-by-step explanation:

1. Equation of a circle:

(x - h)² + (y - k)² = r²

where (h, k) is the center and r is the radius.

If (h, k) is (2, 8) and r = 10:

(x - 2)² + (y - 8)² = 100

2. The vertex and focus have the same x-coordinate, so this is a vertical parabola.  Equation of a vertical parabola is:

y = 1/(4p) (x - h)² + k

where (h, k) is the vertex and p is the distance from the vertex to the focus.

If (h, k) is (2, 2) and p = 5-2 = 3:

y = 1/12 (x - 2)² + 2

3. The directrix is a vertical line, so this is a horizontal parabola.  Equation of a horizontal parabola is:

x = 1/(4p) (y - k)² + h

The distance between the directrix and the vertex is the same as p.

If (h, k) is (5, 2) and p = 5-3 = 2:

x = 1/8 (y - 2)² + 5

1 On a trip to Griffith Observatory, Dave rode his bicycle six more than twice as many miles in the afternoon as in the morning. If the entire trip was 57 miles long, then how far did he ride in the morning and in the afternoon?

Answers

Answer:

the answer is he rode 17 miles in the morning and 40 miles in the afternoon

Step-by-step explanation:

so in the afternoon, it says that 6 more than twice as many miles in the afternoon as in the morning. this means that if the morning is x then in the afternoon it will be 2x+6 but it says altogether it is 57 miles so the you have to add x too.

so the equation is 2x+6+x=57

then this should be easy to solve.

2x+6+x=57

3x+6=57

3x=51

x=17

so if the morning is 17 miles then the afternoon will be:

2(17)+6

this equals to 40.

I hope that this is helpful!

Use the change of variables s=x+3y, t=y to find the area of the ellipse x2+6xy+10y2≤1.

Answers

The change in variables s=x+3y, t=y to find the area of the ellipse x²+6xy+10y²≤1 yields; s² +t²≤ 1.

Substitution of variables

It follows from the equations given that;

s = x +3y, x = s -3yt = y

Hence, it follows from substitution that;

(s-3t)² +6(s-3t)t +10t² ≤ 1

s² -6st +9t² +6st-18t² +10t² ≤ 1

s²+t² ≤ 1

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Final answer:

By applying a change of variables to the ellipse equation x2+6xy+10y2≤1, this simplifies to the standard ellipse equation from which the area, π*sqrt(10), can be determined using the standard formula for the area of an ellipse.

Explanation:

To find the area of the ellipse defined by the equation x2+6xy+10y2≤1, we can begin by using the provided change of variables, s = x + 3y and t = y. This transformation simplifies the equation of the ellipse to: (s^2) / 10 + (t^2) ≤ 1.

Now the expression looks like the standard equation of an ellipse, where 'a' (the radius on the x-axis) is sqrt(10) and 'b' (the radius on the y-axis) is 1. The area 'A' of an ellipse is given by 'A=πab'. Substituting 'a' and 'b' into the formula gives us 'A = π*sqrt(10)*1 = π*sqrt(10)'

This indicates that the area of the ellipse with the change of variables s=x+3y, t=y for the equation x2+6xy+10y2≤1 is π*sqrt(10).

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A bag contains 8 blue marbles, 6 green marbles, 12 yellow marbles and 10 orange marbles. A marble is drawn from at randm of the bag, what is the probibilty that the marble will not be blue?

Answers

8+6+12+10 = 36

6+12+10 = 28

28/36

7/9

Hope this helps ❤️

What is the measure of ∠PQR ? Enter your answer in the box. ° A triangle with one angle measuring 80 degrees and one angle measuring 70 degrees.

Answers

Answer:

∠PQR=30°

Step-by-step explanation:

I assuming that the measure of angle PQR is the third internal angle of the triangle

Remember that

The sum of the internal angles of a triangle must be equal to 180 degrees

80°+70°+∠PQR=180°

150°+∠PQR=180°

∠PQR=180°-150°

∠PQR=30°

Answer:

The answer is 30 degrees

Step-by-step explanation:

(80+70) - 180 = 30

because all the angles should add up to 180 degrees so to double check your answer you do 30+70+80=180

A life scientist worksheet has the names of 36 animals of these 18 fed on seeds 15 feed on insects and 6 feed on both seed and insects a student randomly selects one animal for a study What is the probability that the chosen animal feeds on seeds or insects or both

Answers

Answer:

11/12

Step-by-step explanation:

18/36 + 15/36= 33/36 = 11/12

Answer:

The  probability that the chosen animal feeds on seeds or insects or both is:

                [tex]\dfrac{3}{4}[/tex]

Step-by-step explanation:

Let A denote the event that the animal feed on seeds.

B denote the event that the animal feed on insects

and A∩B denote the event that the animal feed on both seed and insects.

and A∪B denote the event that the animal feeds on seeds or insects or both.

Let P denote the probability of an event.

Now, based on the information from the question we have:

[tex]P(A)=\dfrac{18}{36}\\\\P(B)=\dfrac{15}{36}\\\\P(A\bigcap B)=\dfrac{6}{36}[/tex]

Now, we know that:

[tex]P(A\bigcup B)=P(A)+P(B)-P(A\bigcap B)[/tex]

Hence, on putting the values we have:

[tex]P(A\bigcup B)=\dfrac{18}{36}+\dfrac{15}{36}-\dfrac{6}{36}\\\\\\P(A\bigcup B)=\dfrac{18+15-6}{36}\\\\\\P(A\bigcup B)=\dfrac{27}{36}=\dfrac{3}{4}[/tex]

Describe the transformations of the following function. y=tan(2x-π)

Answers

Answer:

To quickly solve this problem, we can use a graphing tool or a calculator to plot the equation.

Please see the attached image below, to find more information about the graph

The equation is:

y = tan(2x - π)

y = tan (2*(x-π/2))

We can compare it to its parent function

g(x) = tan(x)

The answer is

Option a.

Horizontal shrink by 1/2 and horizontal shift of π/2 to the right

Jenna used the recipe shown below to make punch for a party orange juice 4 cups pineapple 4 cups red tropical 8 cups ginger ale 16 cups if jenna made half a recipe of punch how many quarts of fruit punch did she make

Answers

Answer:

4 quarts

Step-by-step explanation:

What is the surface area of the cone below?

Answers

For this case we have that by definition, the surface area of a cone is given by:

[tex]SA = \pi * r * S + \pi * r ^ 2[/tex]

Where:

SA: It is the surface area

A: It's the radio

S: It's slant height

Then, replacing the values of the figure in the formula we have:

[tex]SA = \pi * 6 * 15 + \pi * 6 ^ 2\\SA = 90 \pi + 36 \pi\\SA = 126 \pi \ units ^ 2[/tex]

ANswer:

Option A

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