Yay, derivitives
I'mma ignore that x is the shorter side because I don't know which one has to be shorter yet
we need to find the max area
but with 3 sides
area=LW
let's say the sides are z and y
zy=area
and the relatiionship between them is
hmm,
z+2y=1200
because one side has no fencing
so
z+2y=1200
solve for z
z=1200-2y
sub for z in other
(1200-2y)(y)=area
expand
1200y-2y²=area
take derivitive
1200-4y=dy/dx area
max is where dy/dx goes from positive to negative
solve for where dy/dx=0
1200-4y=0
1200=4y
300=y
at y<300, dy/dx<0
at y>300, dy/dx>0
so at y=300, that is the max
then
z=1200-2y
z=1200-2(300)
z=1200-600
z=600
so then
z=600
y=300
300<600
so the shorter side would be y
so then we see our choices and noticed that
erm
I think it is f(x)=1200x-2x²
takind the derivitive yeilds none of the others
so ya, you are right
Answer: $32.81 , rounded would be 32.80
Step-by-step explanation:
Divide 420 by 32
then u multiply that by 2.50
Answer:
Cost of one roll of plain wrapping: 
Cost of one roll of holiday wrapping paper: 
Step-by-step explanation:
Let be "p" the cost in dollars of one roll of plain wrapping paper and "h" the cost in dollars of one roll of holiday wrapping paper.
Based on the information given, we can set up this system of equations:

In order to solve it, we can use the Substitution method. The steps are:
1. Solve for "p" from the first equation:

2. Substitute the above into the second equation and solve for "h":
3. Substitute the value of "h" into
:

8 x 45 = 8(40 + 5) = 320 + 40 = 360
Answer:
X/5 - 5 = f(x) for the domain [0,infinity)
Step-by-step explanation: