Question 468399
I'd recommend on-line help for specific problems, but to really
move ahead at your own pace and fill in the gaps, you need a
good textbook, either new or used, which you can buy on-line.
There are lots of websites for math. Just google the kind of
problem you are having, and there will be lots of choices.
I'd get a real textbook, and not a "made easy" book.