# How do you graph y= sqrt (x-4) ?

Apr 19, 2017

First, we need to find the domain of this equation

There are some rules about square roots, but this is the one we care about today:
No square roots of a negative number

So, we need to find the value of $x$ that gives us a negative number, or one that is less that $0$.
$x - 4 = 0$
add $4$ on both sides
$x = 4$

So, $x = 4$ is the smallest value of $x$ we can square root

Our domain is $\left[4 , \infty\right]$

Other than the shift to the right, our graph should look the same as the normal $\sqrt{x}$:
graph{y=sqrt(x-4)}