Enter an equation or problem
Camera input is not recognized!

Solution - Absolute value equations

Exact form: b=5,-13
b=5 , -\frac{1}{3}
Decimal form: b=5,0.333
b=5 , -0.333

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
|b+3|=|2b2|
without the absolute value bars:

|x|=|y||b+3|=|2b2|
x=+y(b+3)=(2b2)
x=y(b+3)=(2b2)
+x=y(b+3)=(2b2)
x=y(b+3)=(2b2)

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||b+3|=|2b2|
x=+y , +x=y(b+3)=(2b2)
x=y , x=y(b+3)=(2b2)

2. Solve the two equations for b

10 additional steps

(b+3)=(2b-2)

Subtract from both sides:

(b+3)-2b=(2b-2)-2b

Group like terms:

(b-2b)+3=(2b-2)-2b

Simplify the arithmetic:

-b+3=(2b-2)-2b

Group like terms:

-b+3=(2b-2b)-2

Simplify the arithmetic:

-b+3=-2

Subtract from both sides:

(-b+3)-3=-2-3

Simplify the arithmetic:

-b=-2-3

Simplify the arithmetic:

-b=-5

Multiply both sides by :

-b·-1=-5·-1

Remove the one(s):

b=-5·-1

Simplify the arithmetic:

b=5

10 additional steps

(b+3)=-(2b-2)

Expand the parentheses:

(b+3)=-2b+2

Add to both sides:

(b+3)+2b=(-2b+2)+2b

Group like terms:

(b+2b)+3=(-2b+2)+2b

Simplify the arithmetic:

3b+3=(-2b+2)+2b

Group like terms:

3b+3=(-2b+2b)+2

Simplify the arithmetic:

3b+3=2

Subtract from both sides:

(3b+3)-3=2-3

Simplify the arithmetic:

3b=2-3

Simplify the arithmetic:

3b=-1

Divide both sides by :

(3b)3=-13

Simplify the fraction:

b=-13

3. List the solutions

b=5,-13
(2 solution(s))

4. Graph

Each line represents the function of one side of the equation:
y=|b+3|
y=|2b2|
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.