Answer:
x = 16
Step-by-step explanation:
Verticle angles are always congruent, so:
(8x + 15) = 143
Now, we can solve to isolate x:
8x + 15 - 15 = 143 - 15 (subtract 15 from both sides)
8x/8 = 128/8 (divide both sides by 8)
x = 16
You can always plug in the value of x to the original equation to check your answer:
8(16) + 15 = 143
