Question

I do t know how to do it

Answer 1

We know: the sum of the angles measures in a triangle is 180°.

Therefore we have the equation:

64° + 75° + α = 180°

139° + α = 180°       subtract 139° from both sides

α = 41°

α and ∠2 are Supplementary Angles - they add up to 180°.

α + m∠2 = 180°

41° + m∠2 = 180°    subtract 41° from both sides

m∠2 = 139°