All categories

3 years ago

If y varies directly as x and y = 9 when x = –3, find y when x = 40.

Mathematics

1 answer:

DedPeter [7]3 years ago

8 0

Answer:

y = -120

Step-by-step explanation:

Direct variation is

y = kx where k is a constant

9 = k(-3)

Divide each side by -3

9/-3 = k

-3 = k

y = -3x

Let x = 40

y = -3(40)

y = -120

You might be interested in

Solve the amount in picture

ss7ja [257]

It’s 2/25 because 24 x 1/3/100 and you simplify the complex fraction so it’s 24 x 1/300 now reduce the numbers with the greatest common factor 12 so now it’s 2x1/25 then calculate the product 2/25

5 0

2 years ago

Find the vertices and foci of the hyperbola with equation quantity x plus one squared divided by sixteen minus the quantity of y

katrin2010 [14]

Answer:

The vertices are (3 , -5) , (-5 , -5)

The foci are (4 , -5) , (-6 , -5)

Step-by-step explanation:

* Lets study the equation of the hyperbola

- The standard form of the equation of a hyperbola with

center (h , k) and transverse axis parallel to the x-axis is

(x - h)²/a² - (y - k)²/b² = 1

- The length of the transverse axis is 2 a

- The coordinates of the vertices are (h ± a , k)

- The coordinates of the foci are (h ± c , k), where c² = a² + b²

- The distance between the foci is 2c

* Now lets solve the problem

- The equation of the hyperbola is (x + 1)²/16 - (y + 5)²/9 = 1

* From the equation

# a² = 16 ⇒ a = ± 4

# b² = 9 ⇒ b = ± 3

# h = -1

# k = -5

∵ The vertices are (h + a , k) , (h - a , k)

∴ The vertices are (-1 + 4 , -5) , (-1 - 4 , -5)

* The vertices are (3 , -5) , (-5 , -5)

∵ c² = a² + b²

∴ c² = 16 + 9 = 25

∴ c = ± 5

∵ The foci are (h ± c , k)

∴ The foci are (-1 + 5 , -5) , (-1 - 5 , -5)

* The foci are (4 , -5) , (-6 , -5)

4 0

3 years ago

Read 2 more answers

The senior class want to play a practical joke on the principal, who was a former college basketball star. They want to fill his

steposvetlana [31]

The number of basketball that will fill up the entire office is approximately 16,615.

Recall:

Volume of a spherical shape = $\frac{4}{3} \pi r^3$

Volume of a rectangular prism = $l \times w \times h$

Given:

Diameter of basketball = 9.5 in.

Radius of the ball = 1/2 of 9.5 = 4.75 in.

Radius of the ball in ft = 0.4 ft (12 inches = 1 ft)

Dimension of the office (rectangular prism) = 20 ft by 18 ft by 12 ft

First, find the volume of the basketball:

Volume of ball = $\frac{4}{3} \pi r^3 = \frac{4}{3} \times \pi \times 4.75^3\\$

Volume of basketball = $448.92 $ in^3$

Convert to $ft^3$

$1728 $ in.^3 = 1 $ ft^3$

Therefore,

Volume of basketball = $\frac{448.92}{1728} = 0.26 $ ft^3$

Find the volume of the office (rectangular prism):

Volume of the office = $20 \times 18 \times 12 = 4,320 $ ft^3$

Number of basket ball that will fill the office = Volume of office / volume of basketball

Thus:

Number of basket ball that will fill the office = $\frac{4,320}{0.26} = 16,615$

Therefore, it will take approximately 16,615 balls to fill up the entire office.

Learn more here:

brainly.com/question/16098833

6 0

2 years ago

Which equation below is equivalent to sin C=h/a ?

qaws [65]

Answer:

D. is the answer

Step-by-step explanation:

8 0

3 years ago

How many gal is in 32 qt?

spin [16.1K]

There are 8 gallons in 32 quarts becuase 4 quarts = 1 gallon so 32 divided by 4 is 8. Hope this helped! :)

6 0

3 years ago