Question

Factor the expression.
Show your work

x²+3xy−18y²

Answer 1

(x + 6y)(x - 3y)

Explanation:

Given

x² + 3xy - 18y²

Consider the factors of the coefficient of the y² term (- 18) which sum to give the coefficient of the xy- term (+ 3)

The factors are + 6 and - 3 , since

6 × - 3 = - 18 and 6 - 3 = + 3 , then

x² + 3xy - 18y² = (x + 6y)(x - 3y)