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WooBin
simplify 2x^2−x−3
ok - sorry to factor these you need to find two numbers with a product of -3 and a sum of 2* one of numbers + other number which gives -1 here they are -3 and +1 and you multiply the +1 by 2 to give you -3 +2(1) = -1
i do these by making 3 columns as follows 2x -3 -1x (aim for this) ------------------------- 2 X x -3 * +1 -3 + 1*2 = -1