Question

In ΔPQR, PQ = PR and the value of ∠QPR is equal to half of external angle at R. What is the value (in degrees) of ∠QPR?

• A. 30
• B. 45
• C. 60
• D. 55

Answer 1

Answer:

C. 60

external angle at R = x

∠QPR = (x/2) 

∠PRQ = (180 - x)

∠PQR = (180 - x)

x/2 + 180 - x + 180 - x = 180 

3x/2 = 180 

x = 120 

∠QPR = (x/2) = 120/2 = 60