How do I factorise quadratic equations?
To factorise an expression such as x 2 - 8x + 15, you need to look for two numbers that add up to make -8 and multiply to give 15.
The only option in this case is -5 and -3
(-5)+(-3)=-8and (-5)x(-3)=15as two negative numbers multiply to a positive number.
MG
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