Question

In Triangle A B C, what is the value of x? Triangle A B C. Angle A is 112 degrees. Exterior angle to angle B is 2 x degrees and the exterior angle to angle C is (2 x + 12) degrees.

Answer 1

70º

Explanation:

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Answer 2

70°

Explanation:

∠A =112°,

Exterior angle to angle B is 2x, therefore ∠B = 180 -2x (angle on straight line)

Exterior angle to angle C is 2x + 12, therefore ∠C = 180 -(2x +12) (angle on straight line) = 180 - 12 -2x = 168 - 2x

∠A + ∠B + ∠C = 180 (sum o angles in a triangle)

112 + 180 - 2x + 168 - 2x = 180

460 - 4x = 180

4x = 460 - 180 = 280

x = 280/4 = 70

x = 70°