X2 - X -12 look at what numbers will add together and make 12. (2x6) or (3x4)Then see what of these combinations, when added together, makes -1. you have to consider that one of these values will be negativeIn this case it would be -4 and 3. (-4+3 = -1 and -4x3 = -12)Therefore factorised...(X-4)(X+3)