Question

In the given figure, the measure of ∠B'A'C' is

Options

•  50°

•  60°

•  70°

•  80°

Answer 1

We have to find  B’A’C’

ince triangles are congruent 

So ∠A = ∠A

3X = 2X + 20

X = 20

Now in  A’B’C’

∠A + ∠B + C  = 180° (By property of triangle)

60° + 60° + ∠C = 180°

∠C = 60°

∠A = 2X + 20

`= 2 xx 20° + 20°`

= 40° + 20

 = 60°

Hence (b) B’A’C’ = 60°.