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To factor this quadratic expression, you need to find two numbers that when added give 7/2 and when multiplied give 1. In this case, the factors are irrational and very hard to conjure up mentally. For such cases, we turn to the Quadratic Formula instead. Thus, So if r equals this, then that means that when we add these values, we get 7/2 and when we multiply we should get 1. Let's test this: Yes, both these check out. So we can write the factorization as: But I could never come up with this by mentally factoring it: the quadratic formula is needed. Stephen La Rocque .
 


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