Question

How do you solve the quadratic `-4-2p^2=-40` using any method?

Answer 1

`p=-3sqrt(2)color(white)("XX")orcolor(white)("XX")p=+3sqrt(2)`

Explanation:

Given
`color(white)("XXX")-4-2p^2=-40`

Simplify by multiplying everything on both sides by `(-1)`
`color(white)("XXX")4+2p^2=40`

Subtract `4` from both sides
`color(white)("XXX")2p^2=36`

Divide both sides by `2`
`color(white)("XXX")p^2=18`

Take the square root (giving both a positive and a negative possible solution)
`color(white)("XXX")p=+-sqrt(18)=+-3sqrt(2)`