In a ΔABC, BM and CN are perpendiculars from B and C respectively on any line passing through A. If L is the mid-point of BC, prove that ML=NL.
Given,
In ΔABC,
BM & CN are perpendiculars from B &C
In ∆BLM and ∆CLN
∠BML =∠CNL= 90°
BL=CL [L is mid point of BC]
∠MLB=∠NLC [vertically opposite angles]
∴ ∆BLM=∆CLN
∴ LM = LN (corresponding sides of congruent triangles)