Find the Symmetry f(x)=x^2-4x

$f (x) = x^{2} - 4 x$

Determine if the function is odd, even, or neither in order to find the symmetry.

1. If odd, the function is symmetric about the origin.

2. If even, the function is symmetric about the y-axis.

Find $f (- x)$ .

Find $f (- x)$ by substituting $- x$ for all occurrence of $x$ in $f (x)$ .

$f (- x) = {(- x)}^{2} - 4 (- x)$

Simplify each term.

Apply the product rule to $- x$ .

$f (- x) = {(- 1)}^{2} x^{2} - 4 (- x)$

Raise $- 1$ to the power of $2$ .

$f (- x) = 1 x^{2} - 4 (- x)$

Multiply $x^{2}$ by $1$ .

$f (- x) = x^{2} - 4 (- x)$

Multiply $- 1$ by $- 4$ .

$f (- x) = x^{2} + 4 x$

A function is even if $f (- x) = f (x)$ .

Check if $f (- x) = f (x)$ .

$x^{2} + 4 x$ $\neq$ $x^{2} - 4 x$

Since $x^{2} + 4 x$ $\neq$ $x^{2} - 4 x$ , the function is not even.

The function is not even

A function is odd if $f (- x) = - f (x)$ .

Find $- f (x)$ .

Multiply $x^{2} - 4 x$ by $- 1$ .

$- f (x) = - (x^{2} - 4 x)$

Apply the distributive property.

$- f (x) = - x^{2} - (- 4 x)$

Multiply $- 4$ by $- 1$ .

$- f (x) = - x^{2} + 4 x$

Since $x^{2} + 4 x$ $\neq$ $- x^{2} + 4 x$ , the function is not odd.

The function is not odd

The function is neither odd nor even

Since the function is not odd, it is not symmetric about the origin.

No origin symmetry

Since the function is not even, it is not symmetric about the y-axis.

No y-axis symmetry

Since the function is neither odd nor even, there is no origin / y-axis symmetry.

Function is not symmetric