Find the value of x when x^2-x-6=0

We firstly need to look how to factorise quadratics. (x    )(x    ) By looking at this, we need 2 numbers that add together to make -1. We need 2 numbers that multiply to make -6. To multiply to make -6, we need at least one of these brackets to be negative: (x -  )(x +   ) Combinations of -6 include: -1 x 6, -6 x 1, -2 x 3, -3, x 2 By looking at these, and that we need to make -1, our numbers must be -3 and 2! Therefore: (x - 3)(x + 2) =0 x-3=0, x= 3 x+2=0, x= -2

JR

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