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Two numbers multiply to be -15 and adds to be 2 what are the numbers?

1 Answer

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Assuming x and y are the two numbers,

x + y = 2 \\ x * y = - 15


x + y = 2 \\ x = 2 - y

Substitute that into

(2 - y) * y = - 15 \\ 2y - {y}^(2) = - 15 \\ {y}^(2) - 2y - 15 = 0 \\ (y - 5)(y + 3) = 0 \\ y = 5

Substitute that into

x = 2 - 5 \\ x = - 3

Answer : The two numbers are 5 and - 3.

Hope this helps. - M
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