Answer:
Step-by-step explanation:
Sum of angles of a triangle = 180
So, 56 + 58 + x = 180
114 + x = 180
x = 116
Now ∠ 1 + ∠x = 180 [ straight line angles]
∠ 1 + 66 = 180
∠1 = 180 - 66 = 114°
OR
You can use the rule : Exterior angle = sum of 2 interior opposite angles.
56 + 58 = ∠1
114 = ∠1
