Answer:
x=103°
x = 24°
x=30°
x=75° and y=110°
Explanation:
9. x + x -26 =180
2x = 180+26
x=103°
10. x/2 +7x =180
15x = 360°
x = 24°
11. 3x-5 = x+55
2x = 60°
x=30°
12. x+20+x+10=180
2x +30 =180
x=75°
y+y-40=180
2y = 220
y=110°
note : related with the sum of the angles at a straight line. and corresponding angles, adjacent angles in a traversal.