Question

The point (12, 9) is included in a direct variation. What is the constant of variation?

Answer 1

the formula for direct variation is y=kx. The k is the constant. If you put the x and y values from the ordered pair and solve for k, you'll have the constant.

9=12k

Divide both sides by 12

9/12=k

simplify
k=3/4

Answer 2

direct variation = y = kx
k is the constant variation
Plugin the points
9/12 = 12k/12
3/4 = k

k = 3/4