SOLVING EQUATIONS CONTAINING ABSOLUTE VALUE(S)SOLVING EQUATIONS CONTAINING ABSOLUTE VALUE(S)
Note:
if and only if 
if and only if a+b=3 or a+b=-3
if any only if a+b=+(x+y)
or a+b=-(x+y)
Solve for x in the following equation.
Problem 3.5c:
Answer: 
Solution:
Either
or
Step 1:
Solve
Step 2:
Solve
There are four real answers; 
However all these answers may or may not be
solutions. You must verify that your answers are the solutions to the
original equation.
Step 4:Check the solutions:
Check by substituting 2.24455
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.
Since the left side of the original equation is equal to the right side of
the original equation after we substitute the value 2.24455 for x, then is a solution.
Check the solution 
by
substituting -0.04455 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.
Since the left side of the original equation is not equal to the right side
of the original equation after we substitute the value -0.04455 for x,
then is not a solution.
Check the solution 
by
substituting 2.153565 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.
Since the left side of the original equation is not equal to the right side
of the original equation after we substitute the value 2.153565 for x,
then is not a solution.
Check the solution 
by
substituting x=0.046435 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.
Since the left side of the original equation is not equal to the right side
of the original equation after we substitute the value for x, then is not a solution.
There is one solution:
You can also verify these two real answers by graphing
The graph is formed by subtracting the right side of the original equation from the left side of the original equation. Note that there is one x-intercept at 2.24455. This verifies the solutions.
If you would like to review the solution to problem 3.5d, click on
Solution
If you would like to go back to the problem page, click on Problem
If you would like to go back to the equation table of contents, click on Contents.
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Author:Nancy Marcus