Given:
PQ = 3 cm, PR = 6 cm, ∠Q = 90°
To find:
∠QPR = ? and ∠PRQ = ?
Solution:
In right ΔPQR,
Let ∠PRQ = θ
Also,
(p / h) = sin θ
PQ / PR = sin θ
3 / 6 = sin θ
1/2 = sin θ
We know,
sin 30° = 1/2
So, θ = 30°
∴ ∠PRQ = θ = 30°
Again, in ΔPQR:
∠Q + ∠PRQ + ∠QPR = 180°
90° + 30° + ∠QPR = 180°
120° + ∠QPR = 180°
∠QPR = 60°
Thus,
∠QPR = 60° and ∠PRQ = 30°
