The area of a semicircle is 0.7693 square miles. What is the semicircle's radius?

Substitute the given information into the formula for area of a semi-circle and solve for r.

A = (1/2) πr²

0.7693 mi² = (1/2) πr²

(2*0.7693 mi²) / π = r²

√ ((2*0.7693 mi²) / π) = r ≈ 0.6998 mi

The radius of the semicircle is approximately 0.700 miles