In the diagram PQR is a triangle where the bisectors of interior angle ∠PQR and exterior angle ∠PRT intersect at a point S. If ∠QSR = 45°, then what is the value of ∠QPR ?
In the diagram PQR is a triangle where the bisectors of interior angle ∠PQR and exterior angle ∠PRT intersect at a point S. If ∠QSR = 45°, then what is the value of ∠QPR ? Correct Answer 90°
Given:
⇒ 2y = 2x + ∠QPR
⇒ ∠QPR = 2y – 2x = 2 × (y – x) ----(1)
Again similarly,
∠SRT = ∠RQS + ∠RSQ
⇒ y = x + 45°
⇒ y – x = 45° ----(2)
Using (2) in (1), we get,
∠QPR = 2 × 45° = 90°
∴ the value of ∠QPR is 90°
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Feb 20, 2025