2a(8a-5)=0 show me how to break down for the answer

Since this is an equation you have to get variables and the constants to each side so you would add 5 to the left to cancel the -5 out and REMEMBER TO ALWAYS DO THE SAME TO BOLTH SIDES so add 5 to 0 which is 5 then add the two variables together but DON'T do this on the other side because your just adding to variables which would be 10a so then the problem would look like this 10a=5 then divide booth by 10 so the answer is a=1/2