Question

.Q2. In figure, if I || m, ZABC = ZABD = 40° and
ZBAD = 90°, then prove that angle BCD is an
isosceles triangle.​

Answer 1

In the figure ,if l||m, ∆abc=∆abd=40° and ∆bad =90°,then prove that ∆ bcd is an isosceles triangle

Answer 2

Answer:

It is an isosceles triangle

Step-by-step explanation:

In triangle CAB and Triangle BAD,

∠CAB=∠DAB =90°

∠CAB=∠ABD=40° and

AB is the common side.

∴ Triangle CAB≅Triangle ABD by ASA

By C.P.C.T, ∠ACB = ∠ADB

∴ CB = BD

∴ Triangle BCD is an isosceles Triangle