What two numbers add up to 10 and multiply to 21

Answer:The answer is 3 & 7

Step-by-step explanation:3 x 7 = 21

3 + (7) = 10

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

x2 + 10x + 21 = 0

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

(X + 3) (X + 7)

To summarize, since 3 and 7 multiply to 21 and add up 10, you know that the following is true:

x2 + 10x + 21 = (X + 3) (X + 7)