x^2 - 5x - 12 = 2, solve for x
RHS should always be 0 so start by taking that across.Now we want two numbers, they need to add up to make - 5 and multiply to make -14.Solve for this and we get -7 and +2.Use this information to factorise: (x - 7)(x + 2) = 0One or the other bracket must equal 0 for this to be true, so x must equal 7 or - 2.Then go on to explain quadratic formula for cases where factorisation is not so easy.
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