Question

Write a list of steps that are needed to find the measure of angle B if angle A is 72 and angle C is 113 ( the figure is a triangle :D ).... please help

Answer 1

Triangle has 3 angles, A, B, C. The total interior angle of a triangle is 180. 
180 = A + B + C
180 = 72 + B + 113
180 = B + 185
B = 180 - 185
B = -5

This only proves that the figure is not a triangle because angle B is negative.