Question

Which point is on the graph of a direct variation equation in which k = 1.8?

A. (4, 0.45)
B. (7.2, 4)
C. (4, 7.2)
D. (0.45, 4)

Answer 1

The answer is C. (4, 7.2)

Explanation:

y=kx

y=1.8x

so plug in your x options to see which works

y=1.8(4)

y=7.2

so your answer is C

Answer 2

The direct variation equation is y = kx.

In this case, the equation is y = 1.8x.
Substitute the given points into the equation. If the x and y coordinate of a point satisfies the equation and both sides are equal, then that point is your answer.