how do u find the range of a square root function?

y= 2- square root of "x+3" (answer y is smaller than or equal to 2)
y= 2 square root of "x+1" minus 2 (answer is y less than or equal to 4)

y=6- square root of "x/2" answer y is less than or equal to 6

y= x+ square root of " x-5"

help?

3 multiplied by x end of quantity minus 1 equals negative 4.