Q.

Sides AB and AC and median AD to ∆ABC are respectively proportional to sides PQ and PR and median PM of another triangle PQR. Show that ∆ABC~∆PQR.


Ans.

Produce AD to E such that AD = DE and join EC

Produce PM to N such that PM = MN and join NR

∆ADB≅∆EDC

∴AB=EC

Similarly, PQ=NR

Since, ABPQ=ACPR=ADPM

⇒ECNR=ACPR=AE2PN2

∴∆AEC~∆PNR

⇒∠1=∠2

Similarly, ∠3=∠4

Hence ∠1+∠3=∠2+∠4⇒∠A=∠P

Also, ABPQ=ACPR

∴ ∆ABC~∆PQR