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

1 Answer
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 [4, oo]

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