Question

Write an equation of the direct variation that includes the point (9, -12).

A. y = -1/2 x
B. y=-1½ x
C. y=1/3x
D. y=-3x

Answer 1

none of these

Explanation:

An equation in the form of direct variation is in the form

y = kx

Checking each equation and substituting the point

-12 = -1/2 (9)

-12 = -4.5 not true

-12 = -1 1/2 (9) = -3/2 *9 = -27/2 - 13.5

-12 = -13/5 not true

-12 = 1/3 (9)

-12 = 3 not true

-12 = -3(9)

-12 = -27 not true