Answer:
a = length of the base = 2.172 m
b = width of the base = 1.357 m
c = height = 4.072 m
Step-by-step explanation:
Suppose we want to build a rectangular storage container with open top whose volume is 12 cubic meters. Assume that the cost of materials for the base is 12 dollars per square meter, and the cost of materials for the sides is 8 dollars per square meter. The height of the box is three times the width of the base. What’s the least amount of money we can spend to build such a container?
lets call a = length of the base
b = width of the base
c = height
V = a.b.c = 12
Area without the top:
Area = ab + 2bc + 2ac
Cost = 12ab + 8.2bc + 8.2ac
Cost = 12ab + 16bc + 16ac
height = 3.width
c = 3b
Cost = 12ab + 16b.3b + 16a.3b = 12ab + 48b² + 48ab = 48b² + 60ab
abc = 12 → ab.3b = 12 → 3ab² = 12 → ab² = 4 → a = 4/b²
Cost = 48b² + 60ab = 48b² + 60b.4/b² = 48b² + 240/b
C(b) = 48b² + 240/b
C'(b) = 96b - 240/b²
Minimum cost: C'(b) = 0
96b - 240/b² = 0
(96b³ - 240)/b² = 0
96b³ - 240 = 0
96b³ = 240
b³ = 240/96
b³ = 2.5
b = 1.357m
c = 3b = 3*1.357 = 4.072m
a = 4/b² = 2.172m
Answer:
Step-by-step explanation:
The slope of a line perpendicular to another line is the opposite reciprocal of the slope of the other line, meaning if the slope of the other line is
, then the slope of the line perpendicular is
.
Knowing this, we can start to construct the equation for the line:


To solve for
, we plug in the coordinates of the point that we know the line runs through,
:




Therefore, the slope of the line that is perpendicular ot the line provided in the equation is the following:

Answer:
I believe it is, 30 minutes of running.
Explanation:
If she spends 12 minutes walking, that means she’s done 6 ‘sets’ of two minutes.
Then, you just have to multiply 6 by 5 and then you get 30.
Answer: 32 and 42
Step-by-step explanation:
5j +12
j= 4
j = 6
5(4) + 12
5 times 4 = 20
20 + 12 = 32
5(6) + 12
5 times 6 = 30
30 + 12 = 42
Answer:
3/1 or 3
Step-by-step explanation:
It rises up three and to the side one