What numbers add up to 2 and multiply to get - 15?

Set up 2 equations

A) x + y = 2

B) x * y = - 15

We can change equation B into x = - 15/y and substitute this into equation A

-15/y + y = 2

-15 + y^2 = 2y

y^2 - 2y - 15 = 0

Factoring

(y + 3) * (y-5) = 0

y = - 3 and y = 5

Then solve for x