How do you factor the expression #9x^2+9x+2#?

1 Answer
Dec 24, 2015

Answer:

You look for its roots with the quadratic formula.

Explanation:

We first need #Delta = b^2 - 4ac = 9#. So there are two real roots.

By the quadratic formula, a root is given by the expression #(-b +- sqrtDelta)/2a#. We apply it here.

#x_1 = (-9 - 3)/18 = -2/3# and #x_2 = (-9 + 3)/18 = -1/3#.

So this polynomial is equal to #9(x + 2/3)(x + 1/3)#.