We have the following function:

So if we graph this function we will get the Figure below. Thus, let's study both the equation and the graph to get some conclusions. Therefore, we can assure these statements:
First. The function is defined only for

as shown in the Figure. This is also true because of

where

must be greater (or equal) than zero.
Second. The range of the function are the values of

.
Third. If

creases then

always creases, too.
Answer:
13 level
Step-by-step explanation:
143/55 = 2.6
5 x 2.6 = 13
The solution to the systems of equations is (7, 3)
Given the systems of equations expressed as:
-x + 4y = 5 ....................1
x - 5y = -2 ...................... 2
Add both equations to have:
-x+x + 4y - 5y = 5 - 2
4y-5y = -3
-y = -3
y = 3
Substitute y = 3 into equation 1:
-x + 4(3) = 5
-x + 12 = 5
-x = 5 - 12
-x = -7
x = 7
Hence the solution to the systems of equations is (7, 3)
Learn more on simultaneous equations here: brainly.com/question/148035
Check the picture below.
now, the "x" is a constant, the rocket is going up, so "y" is changing and so is the angle, but "x" is always just 15 feet from the observer. That matters because the derivative of a constant is zero.
now, those are the values when the rocket is 30 feet up above.

Answer:
∠3=95°
∠4=85°
Step-by-step explanation: