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Question
In Δ PQR, bisectors of ∠ PQR and ∠ PRQ meet at I. Prove that I is equidistant from the three sides of the triangle , and PI bisects ∠ QPR .
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Solution
Since I lies on bisector of ∠ R, I is equidistant from PR and QR.
Again I lies on the bisector of ∠ Q , I is equidistant from PQ and QR.
Hence , I is equi distant from alI sides of the triangle.
Therefore, I lies on the bisector of ∠ P i.e ∠ QPR .
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