The perimeter of semicircle is 25.7 feet. what is the semicircle's radius

In trapezoid efgh, m∠hef=(4x2+16)∘ and m∠gfe=(5x2+12)∘. find the value of x so that efgh is isosceles. i'm desperate.

Brent paid for 6 avocados with a $20.00 bill. he received $10.40 in change. construct and solve an equation can be used to find the price , of each avocados

Line ab contains points a(4, 5) and b(9.7). what is the slope of ab?