Answer:
15.) 104 ... I hope angles are not drawn to scale
16.) 144
17.) 37
Explanation:
15.)
3x + 10 = 4x -12
22 = x
so 3x +10 = 76
180 - 76 = t = 104
16.)
2(21) + 36 + 90 + bcd + a = 360
a = 90 - 21 = 69
360 - (2(21) + 36 + 90 + 69) = bcd
bcd = 360 - 237 = 123
angle acd = 21 + bcd = 21 + 123 = 144
17.)
(5x - 7) + 90 + (3x + 1) = 180
8x -6 = 90
8x = 96
x = 12
so 5x - 7 = 53
90 - 53 = angle lmn = 37