Question

How do I find reflections?

Answer 1

Well thats simple. Got to your bathroom and look at a mirror. You'll see your own reflection.

Answer 2

If we have a point of $\left[\begin{array}{ccc}a\\b\end{array}\right]$ and it's reflected by the line x = h,
you'll have the reflection point of $\left[\begin{array}{ccc}2h-a\\b\end{array}\right]$

From the question above, we conclude that
⇒ the point we have
$\left[\begin{array}{ccc}a\\b\end{array}\right] = \left[\begin{array}{ccc}3\\4\end{array}\right]$
⇒ reflected by
x = 1

The reflection point will be
$\left[\begin{array}{ccc}2h-a\\b\end{array}\right]$
$=\left[\begin{array}{ccc}2(1)-3\\4\end{array}\right]$
$=\left[\begin{array}{ccc}2-3\\4\end{array}\right]$
$=\left[\begin{array}{ccc}-1\\4\end{array}\right]$

The reflection point is (-1,4)