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What two numbers add to -7 and multiply to 12?

1 Answer

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a+b=-7 and ab=12

from the first we can say a=-b-7 and using this value for a in the second we get:

(-b-7)b=12

-b^2-7b=12

b^2+7b+12=0

b^2+3b+4b+12=0

b(b+3)+4(b+3)=0

(b+4)(b+3)=0

So the numbers are -3 and -4