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# In the diagram, QR//ST, /PQ/ = /PR/ and < PST = 75o. Find the value of y....

### Question

In the diagram, QR//ST, /PQ/ = /PR/ and < PST = 75o. Find the value of y.

A) 105o

B) 110o

C) 130o

D) 150o

### Explanation:

In $$\bigtriangleup$$ PQR,

Q = S = 75o (Corresponding angle)

R = Q = 75o (Base angles of an isosceles $$\bigtriangleup$$)

But, y + 75o = 180o (Sum of angles in a straight line)

y = 180 - 75

y = 105o

## Dicussion (1)

• In $$\bigtriangleup$$ PQR,

Q = S = 75o (Corresponding angle)

R = Q = 75o (Base angles of an isosceles $$\bigtriangleup$$)

But, y + 75o = 180o (Sum of angles in a straight line)

y = 180 - 75

y = 105o