a pipe cleaner 20cm long. it is bent into a rectangle. use a quadratic model to calculate the dimensions that give the maximum area.

Answers

Answer 1
Answer:

The dimensions that give the maximum area is 5 cm by 5 cm.

Given:

The perimeter of this rectangle is 20 cm, and formula for perimeter is

P= 2(W+L)

P = 20 cm = 2W + 2L.  

Then W + L = 10 cm,

or W = (10 cm) - L.

The area of the rectangle is A = L·W, and is to be maximized.  

On substituting the values, we get A = L[ (10 cm) - L ], or A = 10L - L²

Note that this is the equation of a parabola that opens down.  With coefficients a = -1, b = 10 and C = 0, we find that the x-coordinate of the vertex (which is the x-coordinate of the maximum as well) is

x = -b / (2a).  Subbing 10 for b and -1 for a, we get:

x = -[10] / [2·(-1)] = 10/2, or 5.

This tells us that one dimension of the rectangle is 5 cm.

Since P = 20 cm = 2L + 2W, and if we let L = 5 cm, we get:

20 cm = 2(5 cm) + 2W, or

10 cm = W + 5 cm, or W = 5 cm.

Therefore, choosing L = 5 cm and W = 5 cm results in a square, which in turn leads to the rectangle having the maximum possible area.

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Answer 2
Answer:

Answer:

5 cm by 5 cm

Step-by-step explanation:

The perimeter of this rectangle is 20 cm, and the relevant formula is

P = 20 cm = 2W + 2L.  Then W + L = 10 cm, or W = (10 cm) - L.

The area of the rectangle is A = L·W, and is to be maximized.  Subbing (10 cm) - L for W, we get A = L[ (10 cm) - L ], or A = 10L - L²

Note that this is the equation of a parabola that opens down.  With coefficients a = -1, b = 10 and C = 0, we find that the x-coordinate of the vertex (which is the x-coordinate of the maximum as well) is

x = -b / (2a).  Subbing 10 for b and -1 for a, we get:

x = -[10] / [2·(-1)] = 10/2, or 5.

This tells us that one dimension of the rectangle is 5 cm.

Since P = 20 cm = 2L + 2W, and if we let L = 5 cm, we get:

20 cm = 2(5 cm) + 2W, or

10 cm = W + 5 cm, or W = 5 cm.

Thus, choosing L = 5 cm and W = 5 cm results in a square, which in turn leads to the rectangle having the maximum possible area.


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How can you represent patterns from everyday life by using tables, expressions, and graphs?

Find the sine of ∠A.

Answers

Based on the right-angle triangle shown below, thesine of ∠A include the following: B.) 3/5.

In order to determine the magnitude of angle A, we would apply the basic sine trigonometric ratio because the given side lengths represent the opposite side (CB) and hypotenuse (AB) of a right-angled triangle;

sin(θ) = Opp/Hyp

Where:

  • Opp represent the opposite side of a right-angled triangle.
  • Hyp represent the hypotenuse of a right-angled triangle.
  • θ represent the angle.

Based on sine trigonometric ratio, the magnitude of angle A can be calculated as follows:

sin(θ) = Opp/Hyp

sin(A) = CB/AB

sin(A) = 3/5.

In conclusion, we can reasonably and logically deduce that thesine of angle A (m∠A) is 3/5.

Complete Question:

Find the sine of ∠A.

A.) 3/4

B.) 3/5

C.) 4/5

D.) 4/3

sin A=(opposite leg)/hypotenuse= 3/5=0.6
For angle A , opposite leg is BC=3
Hypotenuse = 5

If f(x) = 3x + 3, g(x) = 3x + 3, and h(x) = x + 3, what is [g o f o h](–5)?A: –30
B: –24
C: –15
D: –6

Answers

Answer:

The correct answer is D. -6    

Step-by-step explanation:

f(x) = 3x + 3

g(x) = 3x + 3

h(x) = x + 3

We need to find : [g o f o h](–5)

⇒ [g o f o h](–5)

⇒  [g o f]h(-5)

⇒ [g o f](-5 + 3)

⇒ [g o f](-2)

⇒ [g]f(-2)

⇒ [g](3 × -2 + 3)

⇒ [g](-6 + 3)

⇒ g(-3)

⇒ 3 × -3 + 3

⇒ -9 + 3

⇒ -6

Therefore, The correct answer is D. -6                

The answer would be -6.
Start by substituting -5 into the 'h' function.
h(-5) = -5 + 3 = -2
Now substitute this answer into the 'f' function.
f(-2) = 3(-2) + 3 = -3
now substitute this answer into the 'g' function
g(-3) = 3(-3) + 3 = -6
D is your answer

How do you factor 8y^3+316

Answers

8y^3+316
divide both sides by 4 (smallest divisable number) just say you tried to factor 2 and 3 and they weren't whole numbers and then you tried 4 and gave you the answer :)
4(2y^3+79)

Mrs. Chen owns two pieces of property. The areas of the properties are 77,120 square feet and 33,500 square feet. 43,560= 1 acre
Find the total number of acres Mrs. Chen owns, to the nearest hundredth of an acre and please explain how to do it.

Answers

First add the two areas of the properties together. 
77120 + 33500 = 412120 square feet
Divide this number by 43560 to get the number of acres.
412120/43560 = 9.46

Answer: 9.46 acres
Okay so there are two pieces of property Mrs. Chen owns, so in order to find the total number of feet, add 77,120 and 33,500.
77,120 + 33,500= 110,620
1 acre= 43,560
To find the total number of acres now, you divide 110,620 ÷ 43,560
and that equals about 2.54.  (Since you asked for the nearest hundredth of an acre)
If I'm wrong, please forgive me.
I notice that you are in high school and I am in middle school, so if I am wrong, I am so sorry. But if I'm correct, I hope this helped!
- Alina (:

a total of 408 tickets were sold for the school play. They were either adult tickets or student tickets. The number of students so the number of tickets sold three times the number of adult tickets sold

Answers

GivenSituation:
=> There are 408 total of ticket sold for a school play
=> 3 times of the tickets are sold to students compare to the adults
=> So the ratio of the given situation is 1 : 3
=> Now, 1 + 3 = 4
Since, we need 4 parts, let’s divide 408 by 4
=> 408 / 4 = 102 – the number of tickets for adults
=> 102 x 3 = 306 – the number of tickets for students
=> 102 : 306




Five cakes cost 4.00 how much do 7 cost

Answers

The cost of 7 cakes will be equal to 5.6.

What is an expression?

The mathematical expression combines numerical variables and operations denoted by addition, subtraction, multiplication, and division signs.

Mathematical symbols can be used to represent numbers (constants), variables, operations, functions, brackets, punctuation, and grouping. They can also denote the logical syntax's operation order and other properties.

Given that the cost of 5 cakes is 4. The cost of 7 cakes will be calculated as,

5 cakes = 4

1 cake = 4 / 5

7 cakes = ( 4 x 7 ) / 5

7 cakes = 5.6

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you need to divide 5/4 and youll get the price for 1 cake (1.25) then just add 2 more times to 5 (6.5) is the total