Question

Suppose y varies directly with x, and y = 8 when x = –6. What direct variation equation relates x and y? What is the value of y when x = –2?

Answer 1

Since y varies directly as x, we have y/x=k. Since y=8 when x=-6, k=8/-6=-4/3. Thus, the equation that relates x and y is:
\[\frac{y}{x}=-\frac{4}{3}\].
Now, substitute x=-2 here and you'll get its corresponding y-value.