Answer:
Step 1
Step-by-step explanation:
You should isolate the variable, not try to get rid of it. Also, you have to divide both sides by the same number or variable(can't divide one side by a and the other side by 7- it has to be the same).
Step 1 was the first mistake
7a = 28
7a/7 = 28/7
a = 4
