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What two numbers multiply into -40, add into -3

 Apr 30, 2020
 #1
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ab = -40     a = -40/b

a+b=-3

-40/b + b = -3

-40 + b^2 = -3b

b^2 +3b-40 = 0            Quadratic Formula  show   b =  -5   or  -8

                                                                   then    a  =    2   or   5           The red numbers work

 Apr 30, 2020

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