Simple but im confused. explain as well

Given:

This is an inequality. Normally when solving inequalities, we treat the inequality like an equal sign. Let's begin to solve. First, let's distribute on the left side. Multiply -2 by everything in the parenthesis:

Now, let's get the x on the left side of the inequality. It doesn't have to be on the left, but it is good practice when graphing inequalities. Add x to both sides. This will cancel the -x on the right:

Now, we need to get x all by itself. Let's add 4 to both sides which will cancel the -4 on the right side. We are now left with:

Now, since x cannot be negative, we need to divide both sides by -1. We are then left with:

NOTE: When dividing by a negative (or multiply by a negative fraction) to solve for x, you must FLIP the inequality at the end. This is why it is: