Answer: 26
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Explanation:
The angles shown are corresponding angles. Notice how they are in the northeast corner of their respective four-corner configuration.
If m is parallel to n, then the corresponding angles are congruent, and we can say...
5x+13 = 143
5x = 143-13 .... subtract 13 from both sides
5x = 130
x = 130/5 .... divide both sides by 5
x = 26
So taking this logic in reverse: if x = 26, then that leads to 5x+13 equal to 143, making the corresponding angles congruent. Therefore, it would lead to lines m and n being parallel.
