Question

In the following figure, find the values of a, b and c.

Answer 1

In figure, 

In ΔPQS, ∠QPS = ∠PQS + ∠PSQ = 180°  ...[Sum of all the angles of a triangle is 180°]

⇒ 55° + 60° + a = 180°

⇒ 115° + a = 180°

⇒ a = 180° – 115° = 65°

Now, a + b = 180°  ...[Linear pair has sum of 180°]

⇒ 65° + b = 180°

⇒ b = 180° – 65° = 115°

In ΔPSR, ∠PSR = ∠SPR + ∠PRS = 180°  ...[Sum of all the angles of a triangle is 180°]

⇒ 115° + c + 40° = 180°

⇒ 155° + c = 180°

⇒ c = 180° – 115° = 25°