Question

What 2 numbers equal -48 but added equal 13?

Answer 1

Explanation:

Let the numbers be
`x,y`:

`xy=-48`
`(a)`

`x+y=13`
`(b)`

Solve
`(a),(b)` simultaneously:

from
`(b)`,
`y=13-x`. Sub this into
`(a)` to get

`x(13-x)=-48`

`13x-x^2=-48`

`x^2-13x-48=0`

`(x-16)(x+3)=0`

`x=-3,16`

When
`x=-3, y=16` and when
`x=16, y=-3`

SOLUTIONS: -3,16