Enter an equation or problem

Camera input is not recognized!

Solution - Absolute value equations

Exact form:

x = 2, 0

x=2 , 0

See steps

Step-by-step explanation

1. Rewrite the equation without absolute value bars

Use the rules:
$| x | = | y |$ → $x = \pm y$ and $| x | = | y |$ → $\pm x = y$
to write all four options of the equation
$| 8 x - 5 | = | 3 x + 5 |$
without the absolute value bars:

$\| x \| = \| y \|$	$\| 8 x - 5 \| = \| 3 x + 5 \|$
$x = + y$	$(8 x - 5) = (3 x + 5)$
$x = - y$	$(8 x - 5) = - (3 x + 5)$
$+ x = y$	$(8 x - 5) = (3 x + 5)$
$- x = y$	$- (8 x - 5) = (3 x + 5)$

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:

$\| x \| = \| y \|$	$\| 8 x - 5 \| = \| 3 x + 5 \|$
$x = + y$ , $+ x = y$	$(8 x - 5) = (3 x + 5)$
$x = - y$ , $- x = y$	$(8 x - 5) = - (3 x + 5)$

2. Solve the two equations for x

11 additional steps

$(8 x - 5) = (3 x + 5)$

Subtract from both sides:

$(8 x - 5) - 3 x = (3 x + 5) - 3 x$

Group like terms:

$(8 x - 3 x) - 5 = (3 x + 5) - 3 x$

Simplify the arithmetic:

$5 x - 5 = (3 x + 5) - 3 x$

Group like terms:

$5 x - 5 = (3 x - 3 x) + 5$

Simplify the arithmetic:

$5 x - 5 = 5$

Add to both sides:

$(5 x - 5) + 5 = 5 + 5$

Simplify the arithmetic:

$5 x = 5 + 5$

Simplify the arithmetic:

$5 x = 10$

Divide both sides by :

$\frac{(5 x)}{5} = \frac{10}{5}$

Simplify the fraction:

$x = \frac{10}{5}$

Find the greatest common factor of the numerator and denominator:

$x = \frac{(2 \cdot 5)}{(1 \cdot 5)}$

Factor out and cancel the greatest common factor:

$x = 2$

9 additional steps

$(8 x - 5) = - (3 x + 5)$

Expand the parentheses:

$(8 x - 5) = - 3 x - 5$

Add to both sides:

$(8 x - 5) + 3 x = (- 3 x - 5) + 3 x$

Group like terms:

$(8 x + 3 x) - 5 = (- 3 x - 5) + 3 x$

Simplify the arithmetic:

$11 x - 5 = (- 3 x - 5) + 3 x$

Group like terms:

$11 x - 5 = (- 3 x + 3 x) - 5$

Simplify the arithmetic:

$11 x - 5 = - 5$

Add to both sides:

$(11 x - 5) + 5 = - 5 + 5$

Simplify the arithmetic:

$11 x = - 5 + 5$

Simplify the arithmetic:

$11 x = 0$

Divide both sides by the coefficient:

$x = 0$

3. List the solutions

$x = 2, 0$
(2 solution(s))

4. Graph

Each line represents the function of one side of the equation:
$y = | 8 x - 5 |$
$y = | 3 x + 5 |$
The equation is true where the two lines cross.

How did we do?

Please leave us feedback.

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.

Solution - Absolute value equations

Step-by-step explanation

1. Rewrite the equation without absolute value bars

2. Solve the two equations for x

3. List the solutions

4. Graph

Why learn this

Terms and topics

Related links

Solution - Absolute value equations

Step-by-step explanation

1. Rewrite the equation without absolute value bars

2. Solve the two equations for x

3. List the solutions

4. Graph

Why learn this

Terms and topics

Related links

Latest Related Drills Solved