Answer:
100°= angle b(VERTICAL OPPOSITE ANGLE)
100°+x°=180°[co interior angle]
x=180°-100°
x=80°
(X + .3X) / (X - 0.5X) = 1.3X/0.5X
1.3/0.5 = 2.6
2.6 x 100 = 260 %
You left out the 9 in the whole equation. The 1st step you had right you just forgot to put +9. 2nd step you are combining the like terms and get 11-26x=-34x+40. Step 3: you are trying to isolate the x on one of the sides. You need to switch the 11 over to the 40 and get 29. Move -34x over to -26x and get 8x. Step 4 all you are doing in dividing 8 from both sides and get 5.
