#1**+1 **

For quadratic Formula

\(x = {-b \pm \sqrt{b^2-4ac} \over 2a}\)

a = 3 b=-12 and c = -663

You can simplify the math.....and maybe see 'in your mind' if you can factor it by first dividing the left and right sides of the equation by 3 to get

x^2 - 4x - 221 =0

Doesn't help me much

use the QF

a = 1 b= -4 c= -221

4+-sqrt(16-4(1)(-221) / 2 = 4+- 30 / 2 ========> 17 or -13

SO factoring would look like (x-17)(x+13) = 0

ElectricPavlov
Oct 29, 2018