Factorise x² + 6x + 8

A quadratic equation is written in the form: ax2 + bx + cTo factorise, we need to know what 2 numbers multiply to make ac and add to make bac= 8b=64 x 2=8 4+2 = 6We replace b for these two numbers so the equation is now: (x2 + 4x )+ (2x + 8)We then factorise these broken down equations:x(x + 4) +2(x + 4)(x + 4) is repeated so we know it’s a factor, and (x + 2) is a factor

LM

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