9514 1404 393
Answer:
x = 65
Explanation:
Label the two points where the diagonal lines intersect the baseline A and B, with A on the left.
Obtuse angle A is the sum of the remote interior angles 53° and 80°, so is 133°. Obtuse angle B is the sum of the remote interior angles 50° and 62°, so is 112°. Angle x° is the third interior angle of the small triangle, so is ...
x° = 180° -(180° -133°) -(180° -112°) = 133° +112° -180° = 65°
x = 65