Determine the domain and range of

y= (radical) x-4

y= (radical) x^2-4

plz help me step by step. I just need to refreash my math, but i forgot how to find it

2 answers

do you mean
y = sqrt(x-4) ???
if so the right side is real only for x>/= +4 so domain is all x >/= +4 and range is all positive y

If the second one is
y = sqrt (x^2-4)
then (x^2-4) is real only for |x|>/=2
so domain is all x </- -2 and all x>/=+2
and again y is always +
how do u figures out the doamin and range???