Question

How do you solve `5+ 3x = - 4x + 40`?

Answer 1

See a solution process below:

Explanation:

Step 1) Subtract `color(red)(5)` and add `color(blue)(4x)` to each side of the equation to isolate the `x` term while keeping the equation balanced:

`5 + 3x - color(red)(5) + color(blue)(4x) = -4x + 40 - color(red)(5) + color(blue)(4x)`

`5 - color(red)(5) + 3x + color(blue)(4x) = -4x + color(blue)(4x) + 40 - color(red)(5)`

`0 + (3 + color(blue)(4))x = 0 + 35`

`7x = 35`

Step 2) Divide each side of the equation by `color(red)(7)` to solve for `x` while keeping the equation balanced:

`(7x)/color(red)(7) = 35/color(red)(7)`

`(color(red)(cancel(color(black)(7)))x)/cancel(color(red)(7)) = 5`

`x = 5`