Question

which equation represents a direct linear variation
a. y = x + 2
b. y = 1/2x
c. y = 1/x
d. y = xsquared

Answer 1

Direct variation is a special kind of linear equation. In direct variation, two quantities, such as time and distance, or hours and pay, increase or decrease at a consistent rate. The consistent rate is also called the constant of variation.

Answer 2

Please clarify: Do you mean 1/(2x) or do you mean (1/2)x? Those parentheses can make a big difference!

What did you expect to find? What does a general equation for "direct variation" look like?