Answer:
x = 12
Explanation:
We will label the unknown interior angle of the triangle d.
14x - 19 + d = 180
14x + d = 199
d = 199 - 14x
199 - 14x + 3x + 9x + 7 - 2 = 180
199 - 2x +5 = 180
204 - 2x = 180
204 = 180 + 2x
2x = 24
4.5m questions
5.9m answers