(1)
substitute y = 3 into the other equation
3 = 2x + 3 ( subtract 3 from both sides )
0 = 2x → x = 0
solution : (x, y) → (0, 3 )
(2)
substitute y = x into the other equation
x = 2x - 5 ( subtract x and add 5 to both sides )
5 = x then y = x so y = 5
solution : (x, y) → (5, 5 )
(3)
substitute y = - 6 into the other equation
- 6 = 4x + 10 ( subtract 10 from both sides )
- 16 = 4x ( divide both sides by 4 )
x = - 4
solution : (x, y) = (- 4, - 6 )