Answer :
y = 2x + 5
x + 2y = 15
x + 2(2x + 5) = 15
x + 2(2x) + 2(5) = 15
x + 4x + 10 = 15
5x + 10 = 15
- 10 - 10
5x = 5
5 5
x = 1
y = 2(1) + 5
y = 2 + 5
y = 7
(x, y) = (1, 7)
x + 2y = 15
x + 2(2x + 5) = 15
x + 2(2x) + 2(5) = 15
x + 4x + 10 = 15
5x + 10 = 15
- 10 - 10
5x = 5
5 5
x = 1
y = 2(1) + 5
y = 2 + 5
y = 7
(x, y) = (1, 7)