Work out the points of intersection of the graphs of y= (x+2)(x-4) and y=3x+6.

3x+6=(x+2)(x-4)

3x+6 = x2-2x-8

x2-5x-14=0

(x-7)(x+2)=0

x=7 so y=27

and x=-2 so y=0

EL

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