The area of a circle with radius is given by the power function . What happens to the area of the circle when the radius is multiplied by 3?
A) The area increases by a factor of 9.
B) The area is also multiplied by 3.
C) The area increases by .
D) Not enough information.
E) The area increases by .

Question

The area of a circle with radius  is given by the power function  . What happens to the area of the circle when the radius is multiplied by 3?
A) The area increases by a factor of 9. 
B) The area is also multiplied by 3. 
C) The area increases by . 
D) Not enough information. 
E) The area increases by .

Quizplus · Accepted Answer

The area of a circle is proportional to the square of its radius. Therefore, if the radius is multiplied by 3, the area will be multiplied by $3^2=9$.

The Area of a Circle with Radius Is Given