Factorize $T = ax^2+bx+c $: Discriminant: $\Delta = b^2 - 4ac$ $\Delta \lt 0 $ impossible! $\Delta = 0 $ : $T = a(x+\frac{b}{2a})^2 $ $\Delta \gt 0$ : $ T =a(x-x_1)(x-x_2)$ with $ x_1 = \frac{-b+\sqrt \Delta}{2a}$ ; $ x_2 =\frac{-b-\sqrt \Delta}{2a} \}$

Got it ! Factorize: !

$\LARGE x^2 - 9x + 18 =$	$\LARGE (x-3)(x-6) $
$\LARGE 2x^2 - 3x -2 =$	$\LARGE 2(x+\frac{1}{2})(x-2) = (2x+1)(x-2) $
$\LARGE 4x^2 - 4x + 1 =$	$\LARGE 4(x-\frac{1}{2})^2 = (2x-1)^2 $
$\LARGE 63x^2 +25x + 2 =$	$\LARGE (9x+1)(7x+2) $
$\LARGE 5x^2 - 4x -2 =$	$\LARGE 5(x-\frac{2+\sqrt{14}}{5})(x-\frac{2-\sqrt{14}}{5}) $
$\LARGE abx^2 - (a^2+b^2)x + ab =$	$\LARGE ab(x-\frac{a}{b})(x-\frac{b}{a}) =(bx-a)(ax-b) $