Question

A direct variation function contains the points (-8, -6) and (12,9). Which equation represents the function?

Answer 1

Answer:

y = $\frac{3}{4} x$

Step-by-step explanation:

Each point is (x,y). So to find the equation, substitute both points into the given choices.

To test the first choice: y = $-\frac{4}{3}x$ substitute -8 into x and -6 into y

-6 = $-(\frac{4}{3})(-8)$

-6(3) = (-4)(-8)

-18 ≠ 32

Since the numbers are not equal this is not the correct equation. Move on to testing the next equation in the same manner.

The third equation y = $\frac{3}{4}x$ satisfies both points

Test for point (-8,-6)

-6 = $(\frac{3}{4})(-8)$

-6(4) = (3)(-8)

-24 = -24

Test for point (12,9)

9 = $(\frac{3}{4})(12)$

9(4) = (3)(12)

36 = 36