Answer: x = 16
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Step-by-step explanation:
On that diagram, the unmarked angle above the (6x-8) is equal to (5x+12). This is because the unmarked angle and the angle marked with (5x+12) are corresponding angles. Corresponding angles must be congruent if you want line m to be parallel to line n.
From here we add up (5x+12) and (6x-8) and set that sum equal to 180. Solve for x
We get the following:
(5x+12)+(6x-8) = 180
5x+12+6x-8 = 180
(5x+6x)+(12-8) = 180
11x+4 = 180
11x = 180-4
11x = 176
x = 176/11
x = 16