Answer: d=$12, b=$1
d represents DVDs
b represets books
Step-by-step explanation:
Whenever you have 2 examples of 2 different things (such as books and dvds), make a systems of equations.
Step 1: Write a system of equations
3d+4b= 40
d+6b= 18
Step 2: Eliminate any letter. I'll just choose d.
To elimiate d, you have to make them both equal to the biggest d variable. In other words, make both d terms equal to 3d. To do this, miultiply the 2nd equation by 3, and keep the 1st one the same.
3d+4b=40
3d+18b= 54
Now, elimiate d, by doing 3d-3d= 0. Now use subtraction to solve for b since we used this to get 3 and 3 to 0.
4b-18b=40-54
-14b= -14
b= -14÷-14
b= 1
Each book costs 1 dollar.
Step 3: Plug in b=1 to find how much each dvd costs (plug into any equation)
3d+4b=40
3d+4(1)=40
3d+4=40
3d=40-4
3d=36
d=36÷3
d=12
Each dvd is $12
Step 4: Checks--plug d=12 and b=1 into any equation
3d+4b=40
3(12)+4(1)=40
36+4=40
40=40
It's correct ✅
Also i know this was answered really late but id appreciate if i could get brainliest as i worked pretty hard for this :) Hope i could help the best i could :D
At a game show, there are 7 people (including you and your friend) in the front
row.
The host randomly chooses 3 people from the front row to be contestants.
The order in which they are chosen does not matter.
How many ways can you and your friend both be chosen?
The combination is solved and the number of ways of choosing the contestants is 10
What are Combinations?The number of ways of selecting r objects from n unlike objects is given by combinations
ⁿCₓ = n! / ( ( n - x )! x! )
where
n = total number of objects
x = number of choosing objects from the set
Given data ,
Out of the 7 people in the front row, we need to choose 3 people to be contestants, and we want to count the number of ways that both you and your friend are chosen.
Since we are choosing 3 people, there are 3 positions to be filled. We can think of this as a combination problem, where we need to choose 2 people out of the 5 remaining people in the front row, to fill the two remaining positions after you and your friend are chosen.
The number of ways to choose 2 people out of 5 is given by the combination formula:
C(5, 2) = 5! / (2! (5 - 2)!) = 10
Hence , there are 10 ways to choose you and your friend, and then choose two additional people to fill the remaining positions
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As a first step in solving the system shown, Yumiko multiplies both sides of the equation 2x – 3y = 12 by 6. By what factor should she multiply both sides of the other equation so that she can add the equations and eliminate a variable? What one-variable equation is she left with after adding?
5x + 6y = 18
2x – 3y = 12
Factor:________
Equation:________x=_________
Answer:
Yumiko should multiply the other equation by 3.
If she adds the two equations she would be left with the variable 'x'.
Step-by-step explanation:
Given the two equations are as follows:
[tex]$ 2x - 3y = 12 \hspace{5mm} \hdots (1) $[/tex]
[tex]$ 5x + 6y = 18 \hspace{5mm} \hdots (2) $[/tex]
It is given that she multiplies the first equation by 6. Therefore, (1) becomes
[tex]$ 12x - 18y = 72 \hspace{15mm} \hdots (a) $[/tex]
Now, note that the sign of the variable 'y' is negative. So, if we make the co-effecient of 'y' equal in both the cases, add them it would result in the elimination of the variable 'y'.
The co-effecient of y in Equation (2) is 6. To make it 18 like it is in Equation (1), we multiply throughout by 3.
Therefore, Equation (2) becomes:
[tex]$ 15x + 18y = 54 \hspace{5mm} \hdots (b) $[/tex]
Now, we add Equation (a) and Equation (b).
[tex]$ \implies 12x - 18y + 15x + 18y = 72 + 54 $[/tex]
[tex]$ \implies 27x = 126 $[/tex]
Factor: 3
Equation: 27x = 126
The locations in a city are mapped out on a grid, where the origin represents the city center. A traffic helicopter travels due north and then due east to get to the location at (-3,4) to the location at (7,13).
About how many fewer units would the helicopter have traveled if it went directly from one location to the other?
Answer:
Helicopter have traveled 5.55 units of distance approximately if it went directly from one location to the other.
Step-by-step explanation:
We are given the following in the question:
A traffic helicopter travels due north and then due east to get to the location at (-3,4) to the location at (7,13).
The attached image shows the path of helicopter.
Distance Formula:
[tex](x_1,y_1), (x_2,y_2)\\\\d = \sqrt{(x_2-x_1)^2 + (y_2-y_1)^2}[/tex]
Distance traveled by helicopter =
[tex]d((-3,4),(-3,13)) + d((-3,13),(7,13))\\\\=\sqrt{(-3+3)^2 + (13-4)^2} + \sqrt{(7+3)^2 + (13-13)^2}\\= 9+10\\= 19 \text{ units}[/tex]
If the helicopter goes directly:
[tex]d((-3,4),(7,13))\\\\=\sqrt{(7+3)^2+(13-4)^2}\\\approx 13.45 \text{ units}[/tex]
Difference in distances =
[tex]19 - 13.45 = 5.55\text{ units}[/tex]
Thus, helicopter have traveled 5.55 units of distance approximately if it went directly from one location to the other.
Answer:
i had this question in a quiz on edge and got a 100% on the quiz
here is your answer
Step-by-step explanation:
The triangles are similar.
What is the value of x?
Enter your answer in the box
Answer:
x=21
Step-by-step explanation:
Each measurment is multiplied by three, so 7 multiplied by 3 is 21
If Taylor checks his pulse for 7 minutes, what is his rate if he counts 518 beat?
Answer: 74beats/per minute
Step-by-step explanation:
Divide 518 by 7
using standard normal distribution tables, the area under the standard normal curve corresponding to Z > -1.62 is:
The area under the standard normal curve corresponding to Z > -1.62 is approximately 0.9474.
Explanation:The question asks for the area under the standard normal curve corresponding to Z > -1.62. Using standard normal distribution tables, we can find this area by finding the area corresponding to Z = -1.62 and subtracting it from 1. Since standard normal distribution tables provide the area to the left of the Z-score, we need to subtract the area from 1 to get the area to the right of the Z-score.
By looking up Z = -1.62 in the standard normal distribution table, we find the area to the left (or below) the Z-score is approximately 0.0526. Therefore, the area to the right (or above) the Z-score is approximately 1 - 0.0526 = 0.9474.
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The height y of a jumping frog can be modeled by y = -16x^2+ 4x, where x is the time in
seconds) since the frog jumped from the ground. Find the roots of the equation when y = 0
Explain what the roots mean in this situation.
Answer:
roots: 0, 1/4time when the height is zeroStep-by-step explanation:
The roots are the values of x that make y=0.
0 = -16x^2 +4x = -4x(4x -1)
The values of x that make the factors zero are solutions to this equation:
x = 0
x = 1/4 . . . . . makes the factor (4x-1) equal to zero
The roots of the equation are x=0 and x=1/4.
__
Since y is height and x is time, when y=0, the frog is on the ground. The roots, then, are the times when the frog is on the ground.
The smaller root is the time when the frog leapt.
The larger root is the time when the frog landed.
The roots of the equation y = -16x² + 4x are x = 0 and x = 1/4,
The given equation y = -16x² + 4x models the height y of the frog as a function of time x in seconds.
To find the roots of this equation when y = 0, we need to solve:
0 = -16x² + 4x
This is a quadratic equation.
Quadratic equations can be solved by factoring, completing the square, or using the quadratic formula.
In this case, factoring is straightforward:
0 = x(-16x + 4)
This gives us two solutions
x=0
x=4/16=1/4
The roots are x = 0 and x = 1/4 seconds.
Interpreting the Roots
The roots of the equation indicate the times when the frog is at ground level (y = 0). At x = 0, the frog has just jumped, and at x = 1/4 seconds, the frog returns to the ground. Therefore, these roots represent the start and the end of the jump respectively.What is the answer
Can someone please help me first answer gets brainlist
Answer:
9=1.375 10=1.625 11=3.3125 12=4.45
H E L P ME ASAP! PLEASE I NEED HELP!
Part a) Wayen's saving before he spend $28 is $30
Part b) Steph's saving after she spend $28 is $8
Step-by-step explanation:
Ratio of Wayen's saving to stephs saving: 5:5
After spending $28
Ratio of Wayen's saving to Stephs saving: 1:4
We can write ratio as:
[tex]\frac{W}{S}=\frac{5}{6}\\Cross\,\,multiply\\6W=5S\,\,eq(1)[/tex]
After spending $28
[tex]\frac{W-28}{S-28}=\frac{1}{4}\\Cross\,\,multiply\\4(W-28)=S-28\,\,eq(2)[/tex]
Part a) Find Wayen's saving before he spend $28
Using both equations to find value of W
Putting value of S from eq(1) into eq(2)
6W/5=S
[tex]4W-112+28=S\\4W-84=S\\Putting\,\,value\,\,of\,\,S\\4W-84=\frac{6W}{5}\\ Multiply\,\,both\,\,sides\,\,by\,\,5\\20W-420=6W\\20W-6W=420\\14W=420\\W=420/14\\W=30[/tex]
So, Wayen's saving before he spend $28 is $30
Part b) Find Steph's saving after she spend $28
First Steph's saving before spending $28 is:
[tex]S=\frac{6W}{5}\\S=\frac{6*30}{5} \\S=36[/tex]
Now, After spending $28
S-28 we get:
36-28= $8
So, Steph's saving after she spend $28 is $8
Keywords: Ratio and proportion
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Mr. Jones operates a dog walking service. He charges $10 plus $25 an hour.
Which equation represents this linear relationship?
Worth 50 points PLZ HELP ASAP
An F note has a frequncy of 689.46Hz calculate the wavelegnth in meters
Use the formula c = λν to determine wavelength
299792458=689.46λ
434822.1188=λ
Hope this helped!
Answer:
try different keywords
Step-by-step explanation:
Which fraction is equivalent to 2/8
Answer:
1/4 4/16 8/32 16/64
Step-by-step explanation:
Answer:
a simplified fraction is 1/4
Step-by-step explanation:
2/8 (divided by) 2/2= 1/4
what is the domain
{(-1,2),(4,6), (8,3),(11,-6)
a)D:{-1,4,8,11}
b)-1,4,11
c)-6,2,3,6
d)-1,-6,2,3
Answer:
a
Step-by-step explanation:
the x of each point in order from least to greatest makes up the domain
PLEASE HELP ASAPPPP ILL DO BRAINLISETT PLSS HELPP
The slope of the line that passes through two points is
(the difference in 'y') divided by (the difference in 'x').
The two points are: (3, -4) and (5, -7)
The difference in 'y' is . . . (-7) - (-4) = -3
The difference in 'x' is . . . (5) - (3) = 2
The slope of the line through those two points is (-3) / (2) .
That's the 3rd choice on the list.
Answer:
The slope of the line that passes through two points is
(the difference in 'y') divided by (the difference in 'x').
The two points are: (3, -4) and (5, -7)
The difference in 'y' is . . . (-7) - (-4) = -3
The difference in 'x' is . . . (5) - (3) = 2
The slope of the line through those two points is (-3) / (2) .
That's the 3rd choice on the list.
Plz Mark Me Brainsliest!!!
5. A spotlight is mounted 7.3 meters high on a pole to illuminate the center of a parking area at
point A. If A is 10.2 meters from the base of the pole,at what angle of depression, 0, should
the spotlight be aimed?
Answer: 54.4°
Step-by-step explanation:
If the spotlight is mounted 7.3 meters high, its height will be 7.3meters.
If A is 10.2 meters from the base of the pole, the base of the pole to the parking area will be 10.2meters
The angle of the depression will be facing the base directly therefore, the base will be the opposite of the triangle formed and the height of 7.3m will be the adjacent.
To get the depression angle, we use the trigonometry identity SOH, CAH, TOA
Since we have opposite and adjacent, we will use "TOA" which means
Tan theta = Opposite/Adjacent
Opposite = 10.2m Adjacent = 7.3
Tan theta = 10.2/7.3
Tan theta = 1.39
theta = arctan 1.39
Theta = 54.4°
The angle of depression that the spotlight should aim at is 54.4°
To find the angle of depression for the spotlight to illuminate point A, one takes the inverse tangent of the ratio of the height of the pole to the distance from the pole to point A (7.3 meters / 10.2 meters).
Explanation:The student has asked to determine the angle of depression that a spotlight should be aimed at to illuminate a specific point on the ground. To find this angle, we use trigonometry, specifically the tangent function, which relates the opposite side (the height of the pole) to the adjacent side (the distance from the base of the pole to point A).
The tangent of the angle of depression (θ) is equal to the opposite side divided by the adjacent side. That is, tan(θ) = height / distance = 7.3 meters / 10.2 meters.
Using a calculator, the angle of depression θ can be found by taking the inverse tangent (or arctan) of 7.3/10.2. Therefore, θ = arctan(7.3/10.2).
Once you calculate this value, you will have the angle of depression at which to aim the spotlight to illuminate point A.
please help answer this if your able two :)) ♡
Answer: y = 3/4 + 8.25
Step-by-step explanation:
1. You already know the slope, 3/4, and the coordinates (-7,3). We could plug these into a y=mx+b equation: 3=3/4(-7) + b
2. Next you need to solve for b. Then you get your answer of 8.25. (I attached my work for that)
3. You plug in 8.25 as your y-intercept or b: y=3/4 + 8.25
Which is larger 17/40 or 8/15
It's easier to figure it out when both fractions have the same denominator, so let's fix that:
17/40*15/15 is 255/600
8/15*40/40 is 320/600
Notice we are multiplying by a factor of 1 to get equivalent fractions
So 8/15 is bigger
Hope this helped!
8/15
when you divide it it comes out to be 0.533 repeating
but when you divide 17/40 it comes out to be 0.425
so .5 is larger then .4
assume that y varies directly with x, then solve.
if y=-6.6 when x=9.9, find y when x=6.6
y=?
Answer:
y = - 4.4
Step-by-step explanation:
from the question
y = -6.6
x = 9.9
y∝ x
y = kx ..... where k is introduced as a constant of proportionality
solve for k
y=-6.6 and x = 9.9
we have,
-6.6 = k × 9.9
-6.6 = 9.9k
divide both sides by 9.9
-6.6/ 9.9 = 9.9k/9.9
-0.667= k
therefore k = - 0.667
now, find y when x = 6.6
from the equation y = kx
y = -0.667 × 6.6
y = - 4.4
Answer:
-4.4
Step-by-step explanation:
x : y
9.9 : -6.6
6.6 : y
9.9/-6.6 = 6.6/y
y = 6.6 × -6.6/9.9
y = -4.4
When 18 is subtracted from 6 times a number the result is -12 what is the number
Answer:
24
Step-by-step explanation:
18-6=12
24=12x2
12-24= -12
Suppose you toss a fair coin 4 times. Let X = the number of heads you get. Find the probability distribution of X.
Answer:1 and 2:4
Step-by-step explanation: Because if it's fair you have a 50 percent chance of heads or tails. and if u write it as a ratio you would get 2_4 you will most likely learn this in 7th grade or 6th
Harry ate 6 candies. Jake ate 2 fewer candies than Harry. How many candies did jake eat?
Answer:
4
Step-by-step explanation:
6 - 2 = 4
Jake ate 2 less than 6 which is how many Harry ate.
Answer:
4
Step-by-step explanation:
the answer is 4 because 6 minus 2 would be 4 so the answer is four
. The Portman's kitchen table is
rectangular. The table is 4 feet wide
and 8 feet long. Mrs. Portman bought a
tablecloth that will cover 56 square feet.
Is the tablecloth large enough to cover
the table? Explain.
Answer:
Yes
Step-by-step explanation:
The tablecloth is large enough as when you multiply 4×8=32 square feet. Thus meaning a 56 square foot table cloth would be enough.
4×8=32
The measures of ∠1, ∠2, and ∠3 are 40%, 12.5%, and 25% of the sum of the angle measures of the quadrilateral. Find the value of x.
The value of x is 81
Step-by-step explanation:
The sum of the interior angles of any quadrilateral is 360°
The measure of ∠1 is 40% of the sum of the angle measures of the quadrilateralThe measure of ∠2 is 12.5% of the sum of the angle measures of the quadrilateralThe measure of ∠3 is 25% of the sum of the angle measures of the quadrilateralWe need to find the value of x∵ The figure have 4 sides
∴ The figure is a quadrilateral
∵ The sum of the measures of the interior angles of a
quadrilateral is 360°
- Add the four angles and equate the sum by 360
∴ m∠1 + m∠2 + m∠3 + x = 360
∵ m∠1 = 40% of the sum of the angle measures of the quadrilateral
∴ m∠1 = 40% × 360 = [tex]\frac{40}{100}[/tex] × 360 = 144°
∵ m∠2 = 12.5% of the sum of the angle measures of the quadrilateral
∴ m∠2 = 12.5% × 360 = [tex]\frac{12.5}{100}[/tex] × 360 = 45°
∵ m∠3 = 25% of the sum of the angle measures of the quadrilateral
∴ m∠3 = 25% × 360 = [tex]\frac{25}{100}[/tex] × 360 = 90°
- Substitute these values in the equation above
∴ 144 + 45 + 90 + x = 360
- Add the like terms in the left hand side
∴ 279 + x = 360
- Subtract 279 from both sides
∴ x = 81°
The value of x is 81
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At a school
number of boys : number of girls = 11 : 9
There are 124 more boys than girls.
Work out the total number of students at the school.
The Total number of students at the school is 1240.
The given ratio is 11 boys : 9 girls,
Let 11x = boys and
9x = girls.
As 124 more boys are there than girls, so
11x - 9x = 124.
2x = 124
x = 62
The actual number of boys = 11x = 11 × 62 = 682
The actual number of girls = 9x = 9 × 62 = 558
Total number of students at the school = 682 boys + 558 girls = 1240 students
What is 25 more than 50 as an expression
Answer:75
Step-by-step explanation: 50 + 25
what is the product of 2/5 and 2/3
Answer:
4/15 or in decimal form its 0.26
Step-by-step explanation:
Answer:
Step-by-step explanation:
0.26
what is b?
12.6=b+4.1
Answer:
b= 8.5
Step-by-step explanation:
To find b, subtract 4.1 to both sides.
12.6= b+4.1
- 4.1 -4.1
8.5= b
Answer:
7.5 = b
Step-by-step explanation:
12.6 - 4.1 = b + 4.1 - 4.1
8.5 = b
factor this polynomial expression x^2-25
Answer:
x^2-25
Step-by-step explanation:
rewrite 25 as 5^2
x^2-5^2
since both terms are perfect squares, factor using the difference of square s formula, a^2-b^2=(a+b)(a-b) where a=x and b=5
(x+5)(x-5)
plz mark me as brainliest if this helped :)
Answer:
[tex]\[(x+5)*(x-5)\][/tex]
Step-by-step explanation:
Given polynomial expression is [tex]\[x^{2}-25\][/tex]
[tex]\[=> x^{2}-5^{2}\][/tex]
This is of the form [tex]\[a^{2}-b^{2}\][/tex]
An expression of this form can be factorized as [tex]\[(a+b)*(a-b)\][/tex]
Here, a = x and b = 5.
Hence the factorized form of the given polynomial expression can be represented as the following product:
[tex]\[(x+5)*(x-5)\][/tex]
the sum of two numbers is 19 and the difference between the two number is 55
The numbers are 37 and -18.
Step-by-step explanation:
Step 1:
Let the numbers be x and y. Given their sum = 19 and difference = 55. Form equations out of it.
⇒ x + y = 19 --------- (1)
⇒ x - y = 55 --------- (2)
Subtract eq(2) from eq(1)
⇒ 2x = 74
⇒ x = 37
Step 2:
Find y.
⇒ y = 19 - x = 19 - 37 = -18