Planes M and N intersect at line d. Line a forms a right angle with line d. Line b is diagonal and crosses line d. Line c is on plane N and is diagonal. Line e is on plane M and is slightly diagonal at the top of the plane. Which are skew lines? Check all that apply.

a and b
c and b
b and e
e and c
a and e
a and c

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

3382-299=3383- ? fill in the blank?

In the figure below, ∠dec ≅ ∠dce, ∠b ≅ ∠f, and segment df is congruent to segment bd. point c is the point of intersection between segment ag and segment bd, while point e is the point of intersection between segment ag and segment df. the figure shows a polygon comprised of three triangles, abc, dec, and gfe. prove δabc ≅ δgfe.