In the figure, line m is parallel to line n, and line t is a transversal crossing both m and n.
(Figure in The Picture!)
a. Using the letters a, b, c, d, and e, name 3 pairs of angles that are congruent and the parallel postulates/theorems that prove they are.
1.
2.
3.

b. If ∠a = 2x - 10 and ∠d = x + 20, solve for x then find the measure of angle c.
x= _____
m∠c = _______