Enter an equation or problem

Camera input is not recognized!

Solution - Absolute value equations

Exact form:

x = - \frac{1}{2}, \frac{1}{10}

x=-\frac{1}{2} , \frac{1}{10}

Decimal form:

x = - 0.5, 0.1

x=-0.5 , 0.1

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
$2 | 4 x - 1 | = 3 | 4 x |$
without the absolute value bars:

$\| x \| = \| y \|$	$2 \| 4 x - 1 \| = 3 \| 4 x \|$
$x = + y$	$2 (4 x - 1) = 3 (4 x)$
$x = - y$	$2 (4 x - 1) = 3 (- (4 x))$
$+ x = y$	$2 (4 x - 1) = 3 (4 x)$
$- x = y$	$2 (- (4 x - 1)) = 3 (4 x)$

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:

$\| x \| = \| y \|$	$2 \| 4 x - 1 \| = 3 \| 4 x \|$
$x = + y$ , $+ x = y$	$2 (4 x - 1) = 3 (4 x)$
$x = - y$ , $- x = y$	$2 (4 x - 1) = 3 (- (4 x))$

2. Solve the two equations for x

16 additional steps

$2 \cdot (4 x - 1) = 3 \cdot 4 x$

Expand the parentheses:

$2 \cdot 4 x + 2 \cdot - 1 = 3 \cdot 4 x$

Multiply the coefficients:

$8 x + 2 \cdot - 1 = 3 \cdot 4 x$

Simplify the arithmetic:

$8 x - 2 = 3 \cdot 4 x$

Multiply the coefficients:

$8 x - 2 = 12 x$

Subtract from both sides:

$(8 x - 2) - 12 x = (12 x) - 12 x$

Group like terms:

$(8 x - 12 x) - 2 = (12 x) - 12 x$

Simplify the arithmetic:

$- 4 x - 2 = (12 x) - 12 x$

Simplify the arithmetic:

$- 4 x - 2 = 0$

Add to both sides:

$(- 4 x - 2) + 2 = 0 + 2$

Simplify the arithmetic:

$- 4 x = 0 + 2$

Simplify the arithmetic:

$- 4 x = 2$

Divide both sides by :

$\frac{(- 4 x)}{- 4} = \frac{2}{- 4}$

Cancel out the negatives:

$\frac{4 x}{4} = \frac{2}{- 4}$

Simplify the fraction:

$x = \frac{2}{- 4}$

Move the negative sign from the denominator to the numerator:

$x = \frac{- 2}{4}$

Find the greatest common factor of the numerator and denominator:

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

Factor out and cancel the greatest common factor:

$x = \frac{- 1}{2}$

14 additional steps

$2 \cdot (4 x - 1) = 3 \cdot - (4 x)$

Expand the parentheses:

$2 \cdot 4 x + 2 \cdot - 1 = 3 \cdot - (4 x)$

Multiply the coefficients:

$8 x + 2 \cdot - 1 = 3 \cdot - (4 x)$

Simplify the arithmetic:

$8 x - 2 = 3 \cdot - (4 x)$

Multiply the coefficients:

$8 x - 2 = - 12 x$

Add to both sides:

$(8 x - 2) + 12 x = (- 12 x) + 12 x$

Group like terms:

$(8 x + 12 x) - 2 = (- 12 x) + 12 x$

Simplify the arithmetic:

$20 x - 2 = (- 12 x) + 12 x$

Simplify the arithmetic:

$20 x - 2 = 0$

Add to both sides:

$(20 x - 2) + 2 = 0 + 2$

Simplify the arithmetic:

$20 x = 0 + 2$

Simplify the arithmetic:

$20 x = 2$

Divide both sides by :

$\frac{(20 x)}{20} = \frac{2}{20}$

Simplify the fraction:

$x = \frac{2}{20}$

Find the greatest common factor of the numerator and denominator:

$x = \frac{(1 \cdot 2)}{(10 \cdot 2)}$

Factor out and cancel the greatest common factor:

$x = \frac{1}{10}$

3. List the solutions

$x = - \frac{1}{2}, \frac{1}{10}$
(2 solution(s))

4. Graph

Each line represents the function of one side of the equation:
$y = 2 | 4 x - 1 |$
$y = 3 | 4 x |$
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