Answer:
1) x = 17, line a parallel to line b
2) x = 18, line a parallel to line b
Step-by-step explanation:
If line a parallel to line b then (10x - 40) + 50 = 180
Solve for x
10x - 40 + 50 = 180
Combine like terms
10x + 10 = 180
10x = 170
x = 17
x = 17, line a parallel to line b
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If line a parallel to line b then 5x - 16 = 74
Solve for x
5x - 16 = 74
5x = 90
x = 18
x = 18, line a parallel to line b
