Graph y=|4-x|

$y = | 4 - x |$

Step 1

Find the absolute value vertex. In this case, the vertex for $y = | 4 - x |$ is $(4, 0)$ .

To find the $x$ coordinate of the vertex, set the inside of the absolute value $4 - x$ equal to $0$ . In this case, $4 - x = 0$ .

$4 - x = 0$

Solve the equation $4 - x = 0$ to find the $x$ coordinate for the absolute value vertex.

Subtract $4$ from both sides of the equation.

$- x = - 4$

Divide each term in $- x = - 4$ by $- 1$ and simplify.

Divide each term in $- x = - 4$ by $- 1$ .

$\frac{- x}{- 1} = \frac{- 4}{- 1}$

Simplify the left side.

Dividing two negative values results in a positive value.

$\frac{x}{1} = \frac{- 4}{- 1}$

Divide $x$ by $1$ .

$x = \frac{- 4}{- 1}$

Simplify the right side.

Divide $- 4$ by $- 1$ .

$x = 4$

Replace the variable $x$ with $4$ in the expression.

$y = | 4 - (4) |$

Simplify $| 4 - (4) |$ .

Multiply $- 1$ by $4$ .

$y = | 4 - 4 |$

Subtract $4$ from $4$ .

$y = | 0 |$

The absolute value is the distance between a number and zero. The distance between $0$ and $0$ is $0$ .

$y = 0$

The absolute value vertex is $(4, 0)$ .

$(4, 0)$

Step 2

The domain of the expression is all real numbers except where the expression is undefined. In this case, there is no real number that makes the expression undefined.

Interval Notation:

$(- \infty, \infty)$

Set-Builder Notation:

${x | x \in ℝ}$

Step 3

For each $x$ value, there is one $y$ value. Select a few $x$ values from the domain. It would be more useful to select the values so that they are around the $x$ value of the absolute value vertex.

Substitute the $x$ value $2$ into $f (x) = | 4 - x |$ . In this case, the point is $(2, 2)$ .

Replace the variable $x$ with $2$ in the expression.

$f (2) = | 4 - (2) |$

Simplify the result.

Multiply $- 1$ by $2$ .

$f (2) = | 4 - 2 |$

Subtract $2$ from $4$ .

$f (2) = | 2 |$

The absolute value is the distance between a number and zero. The distance between $0$ and $2$ is $2$ .

$f (2) = 2$

The final answer is $2$ .

$y = 2$

Substitute the $x$ value $3$ into $f (x) = | 4 - x |$ . In this case, the point is $(3, 1)$ .

Replace the variable $x$ with $3$ in the expression.

$f (3) = | 4 - (3) |$

Simplify the result.

Multiply $- 1$ by $3$ .

$f (3) = | 4 - 3 |$

Subtract $3$ from $4$ .

$f (3) = | 1 |$

The absolute value is the distance between a number and zero. The distance between $0$ and $1$ is $1$ .

$f (3) = 1$

The final answer is $1$ .

$y = 1$

Substitute the $x$ value $6$ into $f (x) = | 4 - x |$ . In this case, the point is $(6, 2)$ .

Replace the variable $x$ with $6$ in the expression.

$f (6) = | 4 - (6) |$

Simplify the result.

Multiply $- 1$ by $6$ .

$f (6) = | 4 - 6 |$

Subtract $6$ from $4$ .

$f (6) = | - 2 |$

The absolute value is the distance between a number and zero. The distance between $- 2$ and $0$ is $2$ .

$f (6) = 2$

The final answer is $2$ .

$y = 2$

The absolute value can be graphed using the points around the vertex $(4, 0), (2, 2), (3, 1), (5, 1), (6, 2)$

$\begin{array}{c} x & y \\ 2 & 2 \\ 3 & 1 \\ 4 & 0 \\ 5 & 1 \\ 6 & 2 \end{array}$

Step 4

Graph y=|4-x|

Related Questions

Support LCMGCF.com by disabling your adblocker.