Answer:
A = 100π cm²
Explanation:
the area (A) of a circle is calculated as
A = πr² ( r is the radius )
we require to find r
the circumference (C) of a circle is calculated as
C = 2πr
given
C = 20π , then
2πr = 20π ( divide both sides by 2π )
r = 10
Then
A = π × 10² = 100π cm²