Enter an equation or problem
Camera input is not recognized!

Solution - Absolute value equations

Exact form: c=12,9
c=\frac{1}{2} , 9
Decimal form: c=0.5,9
c=0.5 , 9

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
|c+8|=|3c+10|
without the absolute value bars:

|x|=|y||c+8|=|3c+10|
x=+y(c+8)=(3c+10)
x=y(c+8)=((3c+10))
+x=y(c+8)=(3c+10)
x=y((c+8))=(3c+10)

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||c+8|=|3c+10|
x=+y , +x=y(c+8)=(3c+10)
x=y , x=y(c+8)=((3c+10))

2. Solve the two equations for c

15 additional steps

-(c+8)=-(-3c+10)

Expand the parentheses:

-c-8=-(-3c+10)

Expand the parentheses:

c8=3c10

Subtract from both sides:

(-c-8)-3c=(3c-10)-3c

Group like terms:

(-c-3c)-8=(3c-10)-3c

Simplify the arithmetic:

-4c-8=(3c-10)-3c

Group like terms:

-4c-8=(3c-3c)-10

Simplify the arithmetic:

4c8=10

Add to both sides:

(-4c-8)+8=-10+8

Simplify the arithmetic:

4c=10+8

Simplify the arithmetic:

4c=2

Divide both sides by :

(-4c)-4=-2-4

Cancel out the negatives:

4c4=-2-4

Simplify the fraction:

c=-2-4

Cancel out the negatives:

c=24

Find the greatest common factor of the numerator and denominator:

c=(1·2)(2·2)

Factor out and cancel the greatest common factor:

c=12

13 additional steps

-(c+8)=-(-(-3c+10))

Expand the parentheses:

-c-8=-(-(-3c+10))

Resolve the double minus:

c8=3c+10

Add to both sides:

(-c-8)+3c=(-3c+10)+3c

Group like terms:

(-c+3c)-8=(-3c+10)+3c

Simplify the arithmetic:

2c-8=(-3c+10)+3c

Group like terms:

2c-8=(-3c+3c)+10

Simplify the arithmetic:

2c8=10

Add to both sides:

(2c-8)+8=10+8

Simplify the arithmetic:

2c=10+8

Simplify the arithmetic:

2c=18

Divide both sides by :

(2c)2=182

Simplify the fraction:

c=182

Find the greatest common factor of the numerator and denominator:

c=(9·2)(1·2)

Factor out and cancel the greatest common factor:

c=9

3. List the solutions

c=12,9
(2 solution(s))

4. Graph

Each line represents the function of one side of the equation:
y=|c+8|
y=|3c+10|
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.