Answer:
Covered: $3712
Still need to pay: $928
Step-by-step explanation:
4/5 --> 0.8 --> 80%
4640 x 0.8 --> 3712
Covered: $3712 (which is 80%)
Still need to pay: $928 (which is 20%)
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
1. A. y and 1.2y are like terms. c they both contain the same term (y) and can therefore be combined.
2. B. 12x+11 (you have to combine the like terms)
3. 15y+18-4
C. 15y+14 (you must distribute the 3 to inside the parentheses, so 3×5y and 3×6)
4. 9(9-3p) (you have to find a common factor between the terms, in this case 9, and you place it on the outside of the parentheses, while dividing that factor from those terms, which are placed in parentheses.