Answer:
x = 8,49 ft
y = 4,24 ft
Step-by-step explanation:
Let x be the longer side of rectangle and y the shorter
Area of rectangle = 36 ft² 36 = x* y ⇒ y =36/x
Perimeter of rectangle:
P = 2x + 2y for convinience we will write it as P = ( 2x + y ) + y
C(x,y) = 1 * ( 2x + y ) + 3* y
The cost equation as function of x is:
C(x) = 2x + 36/x + 108/x
C(x) = 2x + 144/x
Taking derivatives on both sides of the equation
C´(x) = 2 - 144/x²
C´(x) = 0 2 - 144/x² = 0 ⇒ 2x² -144 = 0 ⇒ x² = 72
x = 8,49 ft y = 36/8.49 y = 4,24 ft
How can we be sure that value will give us a minimun
We get second derivative
C´(x) = 2 - 144/x² ⇒C´´(x) = 2x (144)/ x⁴
so C´´(x) > 0
condition for a minimum
Answer:
2.43675e+17
Step-by-step explanation:
sorry used calculator.
but still hope that this is correct.
Answer:
d. physical features and locations tell historians about the ways people lived.
Step-by-step explanation:
I believe this is the correct answer
The figure is made up of a cone and a cylinder.
Diameter = 16 ft
radius = 16÷2 = 8ft
Volume of the cone = 1/3bh
Volume of the cone =

Volume of the cone =

= 402.12
Volume of the cyclinder = bh
Volume of the cylinder =

Volume of the cylinder =

= 1206.37
Total = 402.12 + 1206.37 = 1608.49 cubic feet
Answer:
8) 21 milliliters
i am not completly sure but it is NOT the whole
9) .4 & 40%
7) 9670 feet
10) a) $7200 b)350,000
Step-by-step explanation:
cuz 35% of 60 is 21
cuz 120/300 is .4 and if you take 300 * .4 it equals 120