Material=wall+2*side and material is 40 ft so:
40=w+2s
w=40-2s
Area=ws, using w from above we get:
A=(40-2s)s
A=40s-2s^2
dA/ds=40-4s and d2A/ds2=-4
Since d2A/ds2 is a constant negative acceleration, when dA/ds=0, A(s) is at an absolute maximum.
dA/ds=0 when 4s=40, s=10 ft
And since w=40-2s, w=20 ft
So the dimensions of the pen are 20 ft by 10 ft, with the 20 ft side being opposite the wall. And the maximum possible area is thus 200 ft^2
I say A but you probably arnt gonna trust my answers again...gd luck!! xx
Answer:

Step-by-step explanation:
Given
Tower one = 15.6 cm
Tower two = 18.3 cm
Tower 3 = 13.9 cm.
Required:
Height of the 4th tower
Represent a cube by X; a cylinder by Y and a hexagonal prism by Z
Tower one, a cube with a hexagonal prism = X + Z = 15.6
Tower two, a cube with a cylinder = X + Y = 18.3
Tower 3, a hexagonal prism with a cylinder = Z + Y = 13.9
----- Equation 1
----- Equation 2
----- Equation 3
Subtract equation 1 from 2



---- Equation 4
Add Equation 4 to Equation 3



Divide both sides by 2



Substitute
in Equation 2 and 3
----- Equation 2

Subtract 8.3 from both sides



----- Equation 3

Subtract 8.3 from both sides



So, we have that



The question states that the 4th tower is made up of the three shapes;
This implies that;



The height of the 4th tower is 23.9cm
So u need to calculate 738 as a lines
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