Question

If the radius of a circle is multiplied by 3 what happens to the area of a circle

Answer 1

area = πr^2 so the equation changes to area = π(3r)^2

Answer 2

Area equals pi multiplied by (r squared)
Therefore;
if the Radius is multiplied by 3
Area = pi multiplied by (r*3)^2
Area = pi multiplied by 9 r squared
Thus;
multiplying the radius by 3 increases the area by 3 squared or 9
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==> The area increases by a factor of 9 <==
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I hope this is helpful.