3721.11 – Symmetric Lines

The lines $L$ and $K$ are symmetric to each other with respect to the line $y = x$ . If the equation of $L$ is $y = ax + b$ with $a \neq 0$ and $b \neq 0$ , then the equation of $K$ is

$\dfrac{1}{a}x + b$
$-\dfrac{1}{a}x + b$
$-\dfrac{1}{a}x-\dfrac{b}{a}$
$\dfrac{1}{a}x+\dfrac{b}{a}$
$\dfrac{1}{a}x-\dfrac{b}{a}$

Solution

e. $\dfrac{1}{a}x-\dfrac{b}{a}$

You can pick a couple of values for $a$ and $b$ and graph the lines to verify that your answer is correct.