Quadratic Equations $ax^2+bx+c=0$
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 $2x^2+5x+3$
$\color{#0275d8}{x}$ |
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$\color{#d9534f}{1x}$ |
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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 $3x^2+16x+5$
$x$ |
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$x$ |
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Therefore, $3x^2+16x+5=$
Factorize $6x^2+13x+6$
Therefore, $6x^2+13x+6=$
Factorize $8x^2+2x-15$
Therefore, $8x^2+2x-15=$
Factorize $-4x^2+19x-12$
Therefore, $-4x^2+19x-12=$
Solve for $x$. If there are multiple answers, separate them with commas. Give answers as simplified fractions and not decimals.
$2x^2+7x+6=0 \qquad x=$
$3x^2+8x+4=0 \qquad x=$
$3x^2-7x+4=0 \qquad x=$
$3x^2-5x+2=0 \qquad x=$
$2x^2+7x-49=0 \qquad x=$
$2x^2+7x-72=0 \qquad x=$
$8x^2+17x+2=0 \qquad x=$
$4x^2-19x+12=0 \qquad x=$
$8x^2+6x-9=0 \qquad x=$
$15x^2+11x+2=0 \qquad x=$
$15x^2-7x-30=0 \qquad x=$
$8x^2+42x+49=0 \qquad x=$