9514 1404 393
Answer:
x = 7
Explanation:
We assume the hash marks are intended to indicate both triangles are isosceles. Then the right-end angle of the upper triangle is ...
180° -2(75°) = 30°
Its complement is the supplement of the "missing variable" angle.
90° -30° = 180° -(18x -6)°
18x = 126 . . . . . rearranging (add 18x -60)
x = 7 . . . . . . . . . divide by 18