9514 1404 393
Answer:
99°
Explanation:
If we assume that angles 5 and 7 are vertical angles, they are congruent:
10x -9 = 9x
x = 9 . . . . . . . add 9-9x
Then angles 5 and 7 are ...
(10·9 -9)° = 9·9° = 81°
Angle 6 will be the supplement to this.
angle 6 = 180° -81°
angle 6 = 99°