13X squared + 7X + 12
What about it? Factorise it?
x(x - 7)
X2 - 4= (x + 2)(x - 2)===========
( x2 - 121 ) = (x + 11) times (x - 11)
3x2 - 8x = x(3x - 8)
(x - 3)(2x - 7)
5x2 + 9x + 13 has no real factors.
X squared + 7X + 12?
Factorise it: (x + 5)(3x - 8)
x-8
(x - 16)(x + 2) x = 16 or -2
It is: x(x-3) factorized