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.
We can see the sequence goes by decreasing 9 on each number
so the numbers are
2, -7, -16, -25, -34, -43, -52, -61, -70
so adding all these numbers we get
2-7-16-25-34-43-52-61-70
= -306
hope this helped
Answer:
Step-by-step explanation:
Answer:
x =-4
Step-by-step explanation:
4x+9 = -2x-15
Add 2x to each side
4x+2x +9 = -2x+2x-15
6x+9 = -15
Subtract 9 from each side
6x +9-9=-15-9
6x = -24
Divide each side by 6
6x/6 = -24/6
x = -4
Answer: (12,0)
Steps:
First, put the equation in slope-intercept form.
y=mx+b
1.5x + 4.5y =18
Subtract 1.5x from both sides.
4.5y =-1.5x +18
Divide both sides by 4.5 to isolate y.
y = -1/3x + 4
Then replace y with 0 because the point for the x-intercept is exactly on the x-axis so the y=0.
0 = -1/3x + 4
Subtract 4 from both sides
-4 = -1/3x
Divide both sides by -1/3 to isolate the x
12=x