Enter an equation or problem
Camera input is not recognized!

Solution - Absolute value equations

Exact form: x=-16,-85
x=-16 , -\frac{8}{5}
Mixed number form: x=-16,-135
x=-16 , -1\frac{3}{5}
Decimal form: x=16,1.6
x=-16 , -1.6

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
2|x2|=3|x+4|
without the absolute value bars:

|x|=|y|2|x2|=3|x+4|
x=+y2(x2)=3(x+4)
x=y2(x2)=3((x+4))
+x=y2(x2)=3(x+4)
x=y2((x2))=3(x+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|2|x2|=3|x+4|
x=+y , +x=y2(x2)=3(x+4)
x=y , x=y2(x2)=3((x+4))

2. Solve the two equations for x

14 additional steps

2·(x-2)=3·(x+4)

Expand the parentheses:

2x+2·-2=3·(x+4)

Simplify the arithmetic:

2x-4=3·(x+4)

Expand the parentheses:

2x-4=3x+3·4

Simplify the arithmetic:

2x4=3x+12

Subtract from both sides:

(2x-4)-3x=(3x+12)-3x

Group like terms:

(2x-3x)-4=(3x+12)-3x

Simplify the arithmetic:

-x-4=(3x+12)-3x

Group like terms:

-x-4=(3x-3x)+12

Simplify the arithmetic:

x4=12

Add to both sides:

(-x-4)+4=12+4

Simplify the arithmetic:

x=12+4

Simplify the arithmetic:

x=16

Multiply both sides by :

-x·-1=16·-1

Remove the one(s):

x=16·-1

Simplify the arithmetic:

x=16

16 additional steps

2·(x-2)=3·(-(x+4))

Expand the parentheses:

2x+2·-2=3·(-(x+4))

Simplify the arithmetic:

2x-4=3·(-(x+4))

Expand the parentheses:

2x-4=3·(-x-4)

2x-4=3·-x+3·-4

Group like terms:

2x-4=(3·-1)x+3·-4

Multiply the coefficients:

2x-4=-3x+3·-4

Simplify the arithmetic:

2x4=3x12

Add to both sides:

(2x-4)+3x=(-3x-12)+3x

Group like terms:

(2x+3x)-4=(-3x-12)+3x

Simplify the arithmetic:

5x-4=(-3x-12)+3x

Group like terms:

5x-4=(-3x+3x)-12

Simplify the arithmetic:

5x4=12

Add to both sides:

(5x-4)+4=-12+4

Simplify the arithmetic:

5x=12+4

Simplify the arithmetic:

5x=8

Divide both sides by :

(5x)5=-85

Simplify the fraction:

x=-85

3. List the solutions

x=-16,-85
(2 solution(s))

4. Graph

Each line represents the function of one side of the equation:
y=2|x2|
y=3|x+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.