Q10 of 95 Page 15

In Fig. 14.97, BE⊥AC. AD is any line from A to BC intersecting BE in H, P, Q and R are respectively the mid points of AH, AB and BC. Prove that ∠PQR = 90°

Given,


In ΔABC,


Q, R are the mid points of AB and AC


QR ⎸⎸AC.. (i)


In ΔABH,


Q, P are the mid points of AB and AH respectively,


QP ⎸⎸BH


QP ⎸⎸BE.. (ii)


But AC⌃BE therefore from (i) and (ii)


QP⌃QR


∠PQR = 90∘


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