http://www.purplemath.com/modules/solverad.htm

http://www.khanacademy.org/math/algebra/exponent-equations/radical_equations/v/solving-radical-equations

http://www.ixl.com/math/algebra-1/solve-radical-equations-ii

http://www.mathsisfun.com/algebra/radical-equations-solving.html

http://www.brightstorm.com/math/algebra/radical-expressions-and-equations/solving-radical-equations/