Inverse, Joint and Direct Variation

What ordered pair does a direct variation always go through when graphed?

• (0, 0)

• (1, 0)

• (0, 1)

• (1, 1)

True or False:
An inverse variation is always a curve and a direct variation is always a line?

• True

• False

What is the constant (k) in this inverse variation?
y = 400/x

• x

• y

• 400

• Not enough information given

What is the constant of variation and the slope?

• -3

• 0

• 3

• 2

Which of the following is NOT a direct variation?

• y = -2x

• y = 1/2x

• 2x + 3y = 2

• 3y = 4x

For direct variation, you ______.

• Add

• Subtract

• Multiply

• Divide

• direct variation
• inverse variation
• neither direct nor inverse variation

Suppose y varies directly as x, and y=39 when x=3.  Find the value of y when x=2.

• 26

• 3

• 58.5

• 2

Suppose p varies directly as r, and p varies inversely as t.
t = 20 when p = 4 and r = 2.
Find t when r = 10 and p = -5.

• 80

• -80

• 4

• -20

Suppose a varies jointly as b & c. 
If a = 15 when b = 4
and c = 5,
then find b when a = 60 and c = 5.

• 320

• 225

• 16

• 8