interior angles of a triangle, when added, = 180
so < A + < B + < C = 180
41 + 90 + < C = 180
131 + < C = 180
< C = 180 - 131
< C = 49
< C + < D + < E = 180.....because when added they form a line
49 + 32 + < E = 180
81 + < E = 180
< E = 180 - 81
< E = 99 <======
