Find the supplement of the complement of angle 4 if angle 4 equals 82 degrees

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

Find parametric equations for the line tangent to the curve of intersection of the surfaces at the given point. surfaces: xsquared2plus+2yplus+2zequals=1212 yequals=33 point: left parenthesis 1 comma 3 comma five halves right parenthesis

Which triangle congruence postulate or theorem justifies my claim that the steps i made using construction paper and scissors produce an isosceles triangle? was it sss, sas, asa, aas, or hl?