Degrees of a triangle

GRE Quant Problem Solving
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I solved it in this way 180-(70+50)= 60
So the value of x is 60 but 120 is the answer. I saw the solution. Is my approach wrong?

2

The approach is fine. The inner angles of a triangle always add up to 180, so the bottom right angle is 60°. However, x is the exterior angle. Because it is a flat line on the bottom, x and the interior angle must add up to 180, so 180 - the interior angle (60°) = 120°, so x = 120°.

1 Like
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Thanks for the explanation,I got it