A radical equation is one that starts out with a square root, cube root, or some other root and gets changed into another form to make the solving process easier. A rational equation is one that involves a fractional expression — usually with a polynomial in the numerator and denominator. Avoid these mistakes when working with radical or rational equations:
Forgetting to check for extraneous solutions
Squaring a binomial incorrectly when squaring both sides to get rid of the radical
Distributing correctly when writing equivalent fractions using a common denominator
Eliminating solutions that create a 0 in the denominator