Question 1210723: What two numbers add to -5 and multiply to -12? I have already tried to find a balance, but none of the whole numbers I found multiply equally. I have tried 1 times -12, 2 times -6, 3 times -4, 4 times -3 and 6 times -12. I feel like I'm missing something simple, but I need help.
Found 2 solutions by ikleyn, MathTherapy:
Answer by ikleyn(54060)   (Show Source):
You can put this solution on YOUR website! .
What two numbers add to -5 and multiply to -12? I have already tried to find a balance, but none of the whole numbers
I found multiply equally. I have tried 1 times -12, 2 times -6, 3 times -4, 4 times -3 and 6 times -12. I feel like
I'm missing something simple, but I need help.
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x + y = -5,
xy = -12.
y = -5-x,
x*(-5-x) = -12.
-5x - x^2 = -12,
x^2 + 5x - 12 = 0,
 =  =  =  .
The numbers are  and  . ANSWER
Solved.
This is a standard problem, a standard approach, and a standard solution.
Answer by MathTherapy(10895)  (Show Source):
You can put this solution on YOUR website!
What two numbers add to -5 and multiply to -12? I have already tried to find a balance, but none of the whole numbers I found
multiply equally. I have tried 1 times -12, 2 times -6, 3 times -4, 4 times -3 and 6 times -12. I feel like I'm missing something
simple, but I need help.
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What you're missing is that there're NO 2 WHOLE NUMBERS/INTEGERS, that MULTIPLY to 12, and sum to/differ by 5!
NOT 12 & 1, 6 & 2, NOR 4 & 3. So, the 2 numbers MUST be IRRATIONAL, as Tutor @IKLEYN demonstrates.!
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