Answer:
28.1 units
Step-by-step explanation:
Area of circle= πr², where r is the radius.
Given that the area is 20π,
20π= πr²
Divide both sides by π:
20= r²
Square root both sides:
[tex]r = \sqrt{20} [/tex]
[tex]r = \sqrt{4(5)} [/tex]
[tex]r = ( \sqrt{4} )( \sqrt{5} )[/tex]
[tex]r = 2 \sqrt{5} [/tex]
Circumference of circle= 2πr
Substitute the value of r:
Circumference of the circle
[tex] = 2(\pi)( 2\sqrt{5} )[/tex]
[tex] = 4\pi \sqrt{5} [/tex]
= 28.1 units (3 s.f.)