I stumbled across coolmath.com while seeking a simpler explanation for solving equations with fractions. Coolmath.com covers addition through Trig and Precalculus. I found it easy to follow and think any teen struggling in math can learn from this site.
My only problem with this site is that it has a black background and bright colors. For my son who has migraines, it is difficult to use for more than 5 or 10 minutes at a time. It would be better if the site had a white background. Besides that the website does a good job of explaining difficult math functions and providing extra math practice.
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