1. If f(x) varies directly with x, and f(x) = 12 when x = 8, write the direct linear variation equation.
a.F(x)=8x
b.F(x)=12x
c.F(x)=2/3x
d.F(x)=3/2x
2.Which does not show a direct variation between x and y?
a.y=5x
b.y=6/x
c.y=0.7x
d.y=x/9
3.Find the constant of variation for the relationship shown in the following table:
x 1 2 3 4
y 3 6 9 12