factorise x^2 - 8x -65
Two numbers add/ subtract to make -8Two numbers multiply to make -65. These are 1 and 65 as well as 5 and 13Seeing as 1 and 65 cant add or subtract to make -8 the numbers we'll use are 5 and 13. These also subtract to make -8.Therefore in the form (x=/-a)(x+/-b). Try:(x+13)(x-5) = X2+ 13x -5x-65 -> so this doesnt workHow about we flip the signs within the brackets(x-13)(x+5) =X2-13x +5x -65 = X2-8x-65
KC
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