The value of x to the nearest tenth is 11.1
Explanation:
Using an illustration to make it easy:
Angles with same colours are corresponding angles. Corresponding angles are equal.
This means the 2nd angle with green colour is equal to (9x - 5)°
(9x - 5)° + (7x + 3)° = 180° (sum of angles on a line)
9x - 5 + 7x + 3 = 180
collect like terms:
9x + 7x - 5 + 3 = 180
16x - 2 = 180
16x = 180 - 2
16x = 178
x = 178/16
x = 11.125
The value of x to the nearest tenth is 11.1
