Direct Variation

Find the constant of variation (k)

100

y=3x What is k?

3

200

y=x/2 What is k?

1/2

300

Mr. Barrett's son

Who is Ethan?

400

y=100 x=5 What is k?

20

500

y=1/3 x=1/2 What is k?

2/3

Write equation given y and x

100

y=6 and x=3. Write the direct variation equation.

y=2x

200

The number of students at CHCH, plus or minus 2

174

300

y=256 and x=4. Write the direct variation equation.

y=64x

400

y=500 and x=25. Write the direct variation equation.

y=20x

500

y=1/4 and x=1/8. Write the direct variation equation.

y=2x

Given equation, find x or y

100

If y=2x and x=4, what is y?

8

200

If y=.3x and x=10, what is y?

3

300

The number of CHCH faculty, plus or minus 3

What is 72?

400

If y=.5x and y=6, what is x?

12

500

If y=(1/3)x and y=3, what is x?

9

Is it Direct?

100

The biggest island in the world.

What is Greenland?

200

Is the following a direct variation function? y=(1/2)x

yes

300

Is the following a direct variation function? y=x+2

no

400

Is the following a direct variation function? y=2x-3

no

500

y=x/3

yes

Questions/Definitions

100

The number of bones in the body, plus or minus 5.

What is 206?

200

What is the y-intercept of a direct variation function?

0

300

What is the slope of a direct variation function? (which variable)

k

400

In a direct variation function, which variable is the dependent variable?

y

500

What number/value can k not equal/have?

0