Factorize completely x2 + 12xy + y2 + 3x + 3y - 18
A. (x + y + 6)(x + y -3)
B. (x - y - 6)(x - y + 3)
C. (x - y + 6)(x - y - 3)
D. (x + y - 6)(x + y + 3)
Correct Answer: A
Explanation
\(x^{2} + 2xy + y^{2} + 3x + 3y - 18\)
\(x^{2} + 2xy + 3x + y^{2} + 3y -18\)
\(x^{2} + 2xy - 3x + 6x + y^{2} -3y + 6y -18\)
\(x^{2} + 2xy -3x + y^{2} -3y + 6x + 6y -18\)
\(x^{2} + xy -3x + xy + y^{2} - 3y + 6x + 6y -18\)
x(x + y - 3) + y(x + y - 3) + 6(x + y - 3)
= (x + y - 3)(x + y + 6)
= (x + y + 6)(x + y -3)
