Question

Find the measure of ∠ABC.

Answer 1

∠ ABC = 50°

Explanation:

the exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.

∠ ACD is an exterior angle of the triangle, then

∠ ABC + ∠ BAC = ∠ ACD ( substitute values )

2x + 95 = 145 ( subtract 95 from both sides )

2x = 50

then ∠ ABC = 2x = 50°

Answer 2

∠ABC = 50°

x = 25°

Explanation:

∠ACB = 180 - 145 = 35°

Total of all angles in a triangle = 180°

35° + 95° = 130°

180 - 130 = 50°

We now know 2x = 50°

x = 50/2 = 25°