x + 2y = 3 ----------- (1)
x - y = 6 ------------(2)
Equation (2) - (1) :
-3y = 3 // ║x - x = 0 ║;║ - y - 2y = -3y║ ; ║6 - 3 = 3 ║
y = -1 // ║ ÷ (-3) on both sides ║
Substitute y = -1 into equation (2) :
x - y = 6 // ║ Equation 2║
x - ( -1 ) = 6 // ║ Sub y = -1 into the equation║
x + 2 = 6 // ║ open the bracket ( - ) ( -) = + ║
x = 4 // ║ Take away 2 from both sides║
Answer: x = 4, y = -1
