Marking Brainliest. Can someone please how to do this with a fairly simple explanation? I'm not sure what to do.

Explanation:

In the LS column, you'll have these steps

3x - 1

3*4 - 1

12 - 1

11

Effectively, we replaced x with 4 and then simplified using PEMDAS.

And in the RS column, you'll have these steps

x + 7

4 + 7

11

We get the same thing at the bottom of each column. This shows that we end up with 11 = 11 after simplifying both sides. Therefore, we've confirmed that x = 4 is the solution to 3x - 1 = x + 7