What is the perimeter and area of this shape. Please explain so it helps me in the future. Will give brainliest to whoever answers correctly.

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

Which math sentence can be used to determine if the triangle is a right triangle?

What is the greatest number of parts of a circle that can be formed by cutting the circle with 7 straight cuts? (note: the parts do not have to be equal in size)