Question

Find two integers whose sum is -13 and product is 40

Answer 1

-8 and -5

-8 x -5 = 40
-8 + (-5) = -13

Answer 2

let us say, the numbers are "a" and "b"
their sum is -13
a + b = -13

their product is 40
a * b = 40
`\bf \begin{cases} a+b=-13\\ a\cdot b=40\implies b=(40)/(a)\\ then\\ ------------\\ a+\boxed{b}=-13\implies a+\boxed{(40)/(a)}=-13 \end{cases}`

solve for "a",
what is "b"? well, b = 40/a :)