Answer:
m∠A = 166°
Explanation:
∠B and ∠A are corresponding angles because the two lines are congruent. Therefore:
7x + 40 = 3x + 112
Subtract 3x from both sides:
4x + 40 = 112
Subtract 40 from both sides:
4x = 72
Divide both sides by 4:
x = 18
Plug this in for ∠A:
∠A = 7 (18) + 40
m∠A = 166°