Answer:
Step-by-step explanation:
∠BEF = ∠CFE {Alternate interior angles}
5x - 10 = 4x + 20 {Subtract 4x from both sides}
5x - 4x - 10 = 20
x - 10 = 20 {Add 10 to both sides}
x = 20 +10
x = 30°
