Step: 1
If the sum of two angles is 180°, then, the angles are called supplementary angles.
Step: 2
From the figure, ∠1 and ∠2, ∠2 and ∠3, ∠3 and ∠4, ∠4 and ∠1 form supplementary angles.
Step: 3
∠1 +
∠2 = 180°
[∠1 and ∠2 form supplementary angles.]
Step: 4
125° +
∠2 = 180°
[Substitute ∠1 = 125°.]
Step: 5
∠2 = 180° - 125° = 55°
[Subtract 125° on both the sides.]
Step: 6
∠2 +
∠3 = 180°
[∠2 and ∠3 form supplementary angles.]
Step: 7
55° +
∠3 = 180°
[Substitute ∠2 = 55°]
Step: 8
∠3 = 180° - 55° = 125°
[Subtract 55° on both the sides.]
Step: 9
∠3 +
∠4 = 180°
[∠3 and ∠4 form supplementary angles.]
Step: 10
125° +
∠4 = 180°
[Substitute ∠3 = 125°.]
Step: 11
∠4 = 180° - 125° = 55°
[Subtract 125° on both the sides.]
Correct Answer is : 55°, 125° and 55°