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respectively.
Example-4
A ΔABC is right angled at A. L is a point on BC such that AL ⊥ BC. Prove that ∠BAL =
∠ACB.
Solution:
Given: In ΔABC, ∠A = 90° and AL ⊥ BC
To prove:∠BAL = ∠ACB
Proof:
In ΔABC and ΔLAC, ∠BAC = ∠ALC [each 90°] …(i)
and ∠ABC = ∠ABL [common angle] ………………(ii)
On adding equations. (i) and (ii), we get
∠BAC + ∠ABC = ∠ALC + ∠ABL …(iii)
Again, in ΔABC,
∠BAC + ∠ACB + ∠ABC = 180°(Angle Sum Property of Triangle)
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