Question

How do you solve for `r` in `r-s-12=P`?

Answer 1

See the entire solution process below:

Explanation:

Add `color(red)(s)` and `color(blue)(12)` to each side of the equation to solve for `r` while keeping the equation balanced:

`r - s - 12 + color(red)(s) + color(blue)(12) = P + color(red)(s) + color(blue)(12)`

`r - s + color(red)(s) - 12 + color(blue)(12) = P + s + 12`

`r - 0 - 0 = P + s + 12`

`r = P + s + 12`