What two numbers multiply to 108 and add up to -21?

Here we answer the question: "What two numbers multiply to 108 and add up to -21?"

The answer to your question is:

-12 and -9

Below we illustrate and prove that -12 and -9 multiply to 108 and add up to -21:

-12 × -9 = 108
-12 + -9 = -21

Are you asking because you are trying to figure out how to factor the following quadratic equation?

x² - 21x + 108 = 0

If so, the solution to factor the quadratic equation above is:

(x - 12 ) (x - 9)

To summarize, since -12 and -9 multiply to 108 and add up -21, you know that the following is true:

x² - 21x + 108 = (x - 12 ) (x - 9)

Multiply To One Number and Add Up To Another
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