Question

How do you solve `3r-4=4(r-3)`?

Answer 1

`r = 8`.

Explanation:

You first develop the right side of the equality : `4(r-3) = 4r - 12`. Now you switch all the `r` at one side and the constants on the other side : `3r - 4 = 4(r-3) iff 3r - 4 = 4r - 12 iff 8 = r`.

Answer 2

Expand the right side, then add and subtract to get variable term on one side and constant term on the other.
`r=8`

Explanation:

Given:
`color(white)("XXX")3r-4=4(r-3)`
Expand right side
`color(white)("XXX")3r-4=4r-12`
Subtract `3r` from both sides
`color(white)("XXX")-4=r-12`
Add `12` to both sides
`color(white)("XXX")8=rcolor(white)("XXXXXX")harr r=8`