Please someone help me ...

Actually Welcome to the Concept of the Functions.

Since, the above function is a square root function, we must always keep it's domain as Positive Real numbers, such that it will not went to the imaginary axis, hence

D: R+

Range, for range we equate it to 0 ,

hence we get as,

R: x belong from 0 to positive Infinite

As, x---> infinite, f(x) ---> - infinite

As, x----> 0 , f(x) -----> 0

increasing interval, we have to differentiate it, we get as

-4 to 0

Decreasing interval is 0 to infinite

the slope of the line is 60

one point on the line is (40,10)

step-by-step explanation:

in the equation outside the parenthesis the equation always tells you the slope. in this case it is 60.

in the parenthesis is also says 40 which is x because it is near the x and 10 is y because it is near y.