Links to Purplemath©
Below, are some links to an excellent Algebra and graphing review website, Purplemath©. Use it, if you need to brush up on some elementary algebra. While I've included some of the pages that are likely to be of most use, there are tens more to have a look at and work through. Do take note of the site's terms-of-use policy.
Purplemath© term-of-use policy
Purplemath© Homework Guidelines (some great advice on how to be careful when doing algebra)
Purplemath© solving linear equations I & II
Purplemath© straight-line equations I & II
Purplemath© slope of a straight line I & II