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Since $(x+a)(x+b)=x^2+(a+b)x+ab$, when we are factorising a quadratic, such as $x^2+cx+d$, we must find the numbers $a$ and $b$ such that $c=a+b$ and $d=ab$.

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In the case of $\\simplify{x^2+{linear}x+{const}}$ we ask

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what two numbers add to give $\\var{linear}$ and multiply to give $\\var{const}$? 

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Therefore the numbers must be $\\var{a}$ and $\\var{b}$, that is 

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$\\simplify{x^2+{linear}x+{const}}=(\\simplify{x+{a}})(\\simplify{x+{b}}).$

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You can check this by expanding the binomial product.

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$\\simplify{x^2+{linear}x+{const}}$ = [[0]].

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Ensure you factorise the expression.

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Ensure you factorise the expression.

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Factorise the following into linear factors. That is, write the quadratic as a product of terms that look like $ax+b$ where $a$ and $b$ are real numbers.

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