Question

If a circle has an area of 84π units then what is the measure of its

radius in exact units?
a. 2√21 units
b. √ 54 units
C 10.4 units
d. 108 units

Answer quickly please

Answer 1

• Answer:

a. 2√21 units

• Explanation:

Hi there !

Area formula

A = π·r²

• replace A

84π = πr²

r² = 84π/π

r² = 84

r² = 2²×3×7

r = √2²×3×7

r = 2√3×7

r = 2√21

Good luck !