Answer:
x = 17
Step-by-step explanation:
For the lines to be parallel, then
(8x - 31) and (6x + 3) are alternate angles and congruent, then
8x - 31 = 6x + 3 ( subtract 6x from both sides )
2x - 31 = 3 ( add 31 to both sides )
2x = 34 ( divide both sides by 2 )
x = 17
