SOLVING EQUATIONS CONTAINING VARIABLES UNDER ONE OR MORE RADICALS

EQUATIONS CONTAINING VARIABLES UNDER ONE OR MORE RADICALS

Note:

In order to solve for x, you must isolate x.
In order to isolate x, you must remove it from under the radical.
If there is just one radical in the equation, isolate the radical.
Then raise both sides of the equation to a power equal to the index of the radical.
With these types of equations, sometimes there are extraneous solutions; therefore, you must check your answers.
If the index of the radical is even, many times there will be a restriction on the values of x.

Example 2:

First make a note of the fact that you cannot take the square root of a negative number. Therefore, tex2html_wrap_inline110

Square both sides of the equation.

Subtract 9 from both sides of the equation

Divide both sides of the equation by 2.

The answer is x = 8.

Check the solution by substituting 8 in the original equation for x. If the left side of the equation equals the right side of the equation after the substitution, you have found the correct answer.

If you would like to work another example, click on example.
If you would like to test yourself by working some problems similar to this example, click on problem.

If you would like to go back to the equation table of contents, click on contents.

[Algebra] [Trigonometry] [Geometry] [Differential Equations] [Calculus] [Complex Variables] [Matrix Algebra]

S.O.S MATHematics home page

Do you need more help? Please post your question on our S.O.S. Mathematics CyberBoard.

Author:Nancy Marcus