Enter an equation or problem
Camera input is not recognized!

Solution - Absolute value equations

Exact form: =12,72
=\frac{1}{2} , \frac{7}{2}
Mixed number form: =12,312
=\frac{1}{2} , 3\frac{1}{2}
Decimal form: =0.5,3.5
=0.5 , 3.5

Other Ways to Solve

Absolute value equations

Step-by-step explanation

1. Rewrite the equation without absolute value bars

Use the rules:
|x|=|y|x=±y and |x|=|y|±x=y
to write all four options of the equation
|+3|=|2x+4|
without the absolute value bars:

|x|=|y||+3|=|2x+4|
x=+y(+3)=(2x+4)
x=y(+3)=(2x+4)
+x=y(+3)=(2x+4)
x=y(+3)=(2x+4)

When simplified, equations x=+y and +x=y are the same and equations x=y and x=y are the same, so we end up with only 2 equations:

|x|=|y||+3|=|2x+4|
x=+y , +x=y(+3)=(2x+4)
x=y , x=y(+3)=(2x+4)

2. Solve the two equations for

7 additional steps

(3)=(-2x+4)

Swap sides:

(-2x+4)=(3)

Subtract from both sides:

(-2x+4)-4=(3)-4

Simplify the arithmetic:

-2x=(3)-4

Simplify the arithmetic:

2x=1

Divide both sides by :

(-2x)-2=-1-2

Cancel out the negatives:

2x2=-1-2

Simplify the fraction:

x=-1-2

Cancel out the negatives:

x=12

6 additional steps

(3)=-(-2x+4)

Expand the parentheses:

(3)=2x-4

Swap sides:

2x-4=(3)

Add to both sides:

(2x-4)+4=(3)+4

Simplify the arithmetic:

2x=(3)+4

Simplify the arithmetic:

2x=7

Divide both sides by :

(2x)2=72

Simplify the fraction:

x=72

3. List the solutions

=12,72
(2 solution(s))

4. Graph

Each line represents the function of one side of the equation:
y=|+3|
y=|2x+4|
The equation is true where the two lines cross.

Why learn this

We encounter absolute values almost daily. For example: If you walk 3 miles to school, do you also walk minus 3 miles when you go back home? The answer is no because distances use absolute value. The absolute value of the distance between home and school is 3 miles, there or back.
In short, absolute values help us deal with concepts like distance, ranges of possible values, and deviation from a set value.