Answer:
The answer to your question is:
x = 21
y = 4
∡ = 75° and 105°
Explanation:
Process
3(x + y)° + 5x = 180 supplementary angles
3(x + y) = 4x - 9 corresponding angles
Expanding
3x + 3y + 5x = 180 (1) Like terms
3x + 3y = 4x - 9 (2)
8x + 3 y = 180 (1)
8 ( -x + 3 y = -9) (2) Multiply by 8
8x + 3y = 180 (1)
-8x +24y = -72 (2) Elimitation method
27 y = 108
y = 108 / 27
y = 4
8x + 3 (4) = 180
8x +12 = 180
8x = 168
x = 21
3(21 + 4) = 3(25) = 75°
5(21) = 105°