Answer:
x = 11
Step-by-step explanation:
Lines are parallel. 5x + 10 and 10x + 5 are supplements of each other.
Move 5x+ 10 to the corresponding position on the figure. It will be next to 10x + 5 and form a linear pair with 10x + 5. A linear pair form a straight angle or two supplementary angles. Supplementary angles = 180°
Therefore 5x +10 + 10x + 5 = 180°
15x + 15 = 180°
15x = 180 - 15
15x = 165
x = 11
