8
x - y = 4, x = y + 4 (equation 1)
x^2 - xy = 12 (equation 2)
replace x in the equation 2 we get:
(y + 4)^2 -y(y +4) = 12
y^2 + 8y + 16 - y^2 - 4y = 12
4y = 12 - 16 = -4
y = -1
x = -1 + 4 = 3
The solution is (3, -1)
Added 4/15/2014 8:18:21 AM
This answer has been confirmed as correct and helpful.
