Step-by-step explanation:
x + y = 3 (1)
x - 2y = -5 (2)
On subtracting
x + y - (x - 2y) = 3 - (-5)
x + y - x - 3y = 3 + 5
y - 3y = 8
-2y = 8
y = 8/-2
y = -4
From 1
x + (-4) = 3
x - 4 = 3
x = 4 + 3
x = 7
Therefore, (3,4) is not a solution of the equation
