What two numbers multiply to -646 and add up to -21?

Here we answer the question: "What two numbers multiply to -646 and add up to -21?"

The answer to your question is:

-38 and 17

Below we illustrate and prove that -38 and 17 multiply to -646 and add up to -21:

-38 × 17 = -646
-38 + 17 = -21

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

x² - 21x - 646 = 0

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

(x - 38 ) (x + 17)

To summarize, since -38 and 17 multiply to -646 and add up -21, you know that the following is true:

x² - 21x - 646 = (x - 38 ) (x + 17)

Multiply To One Number and Add Up To Another
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