Answer:
x = 9
Explanation:
when two lines intersect, it creates four angles. vertical angles are the angles that are opposite to each other. in the attached image, 1 & 3 are vertical angle pairs, and so are 2 & 4.
since vertical angles are always congruent, 3x - 8 is equal to 2x + 1
3x - 8 = 2x + 1
add 8 to each side
3x = 2x + 9
subtract 2x from each side
x = 9
check your answer:
3x - 8 = 2x + 1
3(9) - 8 = 2(9) + 1
27 - 8 = 18 + 1
19 = 19