Solve x^2 - x - 12
As it is a quadratic, I can use the quadratic equation, or (-b +/- sqrt(b2-4ac))/2aHere our a = 1, b = -1 and c = -12. Substitute into the quadratic equation, this becomes (1 +/- sqrt(1 + (4*12))/2 and then (1 +/- sqrt(49))/2Our answers will then be 1/2 + 7/2 and 1/2 - 7/2, which is equivalent to 4 and -3. Therefore our x = 4 and x = -3
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