A radical is not simplified if there is a radical left in the denominator. To eliminate a radical in the denominator, we must rationalize the denominator, which means to multiply the numerator and the denominator by the square root that is in the denominator. If you have a binomial with a square root, multiply by the conjugate. The conjugate is the binomial with the opposite sign between the two terms.
To solve Radical Equations, isolate the radical, then square both sides. Squaring both sides creates a new equation. The solutions to the new equation will not always be solutions of the original equation. Such solutions are called extraneous solutions. In order to find the extraneous solutions, put the equations back into the original equation and see if they work.
Marcos's assignment is p.625 (28-36 ev, 46,48,50,64-70 ev) and p. 632 (2-18 ev, 22-28 ev)