43.600 we leared this in school so the answer should be 43.600
Answer:

Step-by-step explanation:
(-14) ÷ (-34)
14/34
= ⁷/17
Whenever you face the problem that deals with maxima or minima you should keep in mind that minima/maxima of a function is always a point where it's derivative is equal to zero.
To solve your problem we first need to find an equation of net benefits. Net benefits are expressed as a difference between total benefits and total cost. We can denote this function with B(y).
B(y)=b-c
B(y)=100y-18y²
Now that we have a net benefits function we need find it's derivate with respect to y.

Now we must find at which point this function is equal to zero.
0=100-36y
36y=100
y=2.8
Now that we know at which point our function reaches maxima we just plug that number back into our equation for net benefits and we get our answer.
B(2.8)=100(2.8)-18(2.8)²=138.88≈139.
One thing that always helps is to have your function graphed. It will give you a good insight into how your function behaves and allow you to identify minima/maxima points.
Answer:
(2, -2)
Step-by-step explanation:
Given the equation
x - y = 4 ... 1
6x+y = 10 ...2
Add both expressions
x+6x = 4 + 10
7x = 14
x = 14/7
x = 2
Substitute x = 2 into equation 1;
From 1;
x - y = 4
2 - y = 4
y = 2-4
y = -2
Hence the solution to the system of equation is (2, -2)