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

Options
50°
60°
70°
80°
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Solution
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°.
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