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Factorizing $ax^2+bx+c$

Factorizing $ax^2+bx+c$

Expand $\left(\color{#0275d8}{2x}+\color{#d9534f}{3}\right)\left(\color{#d9534f}{x}+\color{#0275d8}{1}\right)=$ $x^2+$ $\color{#0275d8}{x}+$ $\color{#d9534f}{x}+$

$=$ $x^2+$ $x+$

So, to factorize $2x^2+5x+3$
$\color{#0275d8}{x}$ ╳
$\color{#d9534f}{1x}$
where if you cross multiply and add, you get the middle term $5x$

Therefore, $2x^2+5x+3=\left(2x+3\right)\left(x+1\right)$

Practice
Factorize $3x^2+16x+5$
$x$ ╳
$x$
Therefore, $3x^2+16x+5=$

Factorize $6x^2+13x+6$
╳ $3$
Therefore, $6x^2+13x+6=$

Factorize $8x^2+2x-15$
╳ $3$
Therefore, $8x^2+2x-15=$

Factorize $-4x^2+19x-12$
╳
$x$
Therefore, $-4x^2+19x-12=$

Factorize:
$3x^2+7x+4$
$3x^2+8x+4$

$3x^2+13x+12$
$2x^2+x-6$

$3x^2+8x-16$
$2x^2-5x+3$

$3x^2+22x+35$
$2x^2-5x-25$

$2x^2+7x-49$
$4x^2+7x-2$

$5x^2+3x-2$
$5x^2-11x+2$

$25x^2+10x-8$
$12x^2+17x+6$

$12x^2-7x-49$
$15x^2-7x-30$