What is the domain of the function y=sqrtx+6-7

I'm assuming ya mean


alrighty, domain is the numbers  you can use for x without making wierd stuf happen
the only numbers you can't use are the ones that cause a division by 0 or a squaer root of a negative number

no value of x will make a division by 0 but we can have a negative squaer root
solve for where it will be negative and restrict that reigon

the part under the squaer root is x+6
so
x+6<0
minus 6 both sides
x<-6

that is where we begin to see negative squaer roots

so the domain is x≥-6