Answer:
Option 1 is correct
A varies directly with r.
Step-by-step explanation:
The direct variation says that:
\(y \propto x\)
then the equation is in the form of:
\(y = kx\)
where, k is the constant of variation
Given the equation:
\(A = \pi r^2\)
Here, \(\pi\) is constant in the equation.
By above definition we have;
\(A \propto r\)
Therefore, the following correctly describes the variation in the given equation is,
A varies directly with r.
