Find the area of a triangle with a base of 10mm and a height of 8mm

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.

Iwill give ! if m∠a=59 and m∠3=81°, what is m∠b? m∠b= _[blank]_°

Write a fraction less than 1, which has a denominator of 6 and is greater than 3/4 plz answer !