You are solving for x. Isolate the variable, x. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS. Note that:
First subtract the 2 to isolate the 7x. Remember what you do to one side you do to the other, so then you would subtract 2 from 30 as well giving you 7x=28. After that in order to isolate x, you would divide by 7 on both sides giving you x=4.
The cotton gin made it easy for slaves to separate seeds out of the cotton. However, it it increased slave usage all over. It actually increased the use of slavery. The cotton gin just made one part of a slaves job quicker and easier.
