Question

Which equations show a direct variation between x and y when solved for y?
Choose all answers that are correct.
a. y-9=2x+9
b. y=4/7x
c. 4+y=1/3x+4
d. y=3/x

Answer 1

A. if you solve for y, then you get y=2x+18, and that is not direct variation, so it is not 
B. It is direct variation since you only have a slope and the line passes through the origin so it is direct variation
C. If you solve for y, you get y=1/3x. and that is direct variation because the line passes through the origin.
D. That is not direction variation,because that is inverse variation.
So it is B, C