What is the horizontal distance that your bridge must span to clear the ravine?

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

Ineed with angles and the measure of them i have abc a is 65 and b is (3x-10) and c is (2x) find the value of x

Delbert keeps track of total of the total number of points he earns on homework assignments, each of which is worth 60 points. at the end of the semester he has 810 points. write an equation for delbert’s average homework score a in terms of the number of assignments n.