10x² - 9x + 2 = 10x² - 5x - 4x + 2 = 5x(2x - 1) - 2(2x - 1) = (5x - 2)(2x - 1). * (Note that -5 and -4 have a sum of -9; and that their product is +20, which is also the product of +10 and +2. That answers any question of how we knew to split the -9x into -5x and -4x, in the first step, above. This method will work whenever one factorises any factorisable quadratic expression; although I will not attempt here to explain the theory of why.) * The roots are 2/5 and ½. That is, 10x² - 9x + 2 = 0 exactly when, either, 5x - 2 = 0, or 2x - 1 = 0.
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9 - (-1) = +10 positive nine minus negative one equals positive ten
No, it's 10 to the minus nine
negative 9 over 2
-10-(-60)=50 A negative and a negative equals a positive. Therefore, negative ten minus negative sixty is the same as negative ten PLUS sixty. Sixty minus ten equals fifty.
negative 3