1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ZanzabumX [31]
3 years ago
14

An outdoor track consists of a rectangular region with a semi-circle on each end. If the perimeter of the track must be 200 mete

rs, find the dimensions that will make the area of the rectangular region as large as possible.

Mathematics
1 answer:
mars1129 [50]3 years ago
6 0

Answer:

Length = 50m

Width = 31.84m

Step-by-step explanation:

Perimeter of a track = 200m

The perimeter of a track with two semi-circular end and two rectangular regions = P

Perimeter of a semi-circle = ½(2πr)

Length of a rectangle = x

Perimeter of the rectangle = x+x

P = ½(2πr) + ½(2πr)+x + x

P = 2πr + 2x

200 =2πr + 2x

2πr = 200 – 2x

2πr = 2(100 – x)

r = 2(100 – x) / 2π

r = (100-x)/π

total area of the rectangular region =A

A= x(2r)

= (x)2[(100-x)/π]

= 2x[(100-x)/π]

A = (200x – 2x^2)/π

Differentiate A with respect to x

dA/dx = (200 -4x)/π

at critical point, first derivative vanishes(dA/dx = 0)

(200 -4x)/π = 0

-4x =-200

x =-200/-4

x = 50

this means length (x) = 50m

put x=50 into r = (100-x)/π

r= (100-50)/π

r =50/π

width = 2r

width = 2(50/π)

= 2(19.62)

= 31.84m

You might be interested in
Desde la parte más alta de un edificio a 25 m una persona lanza hacia la base un objeto de 150 g con una velocidad de 0.8 m por
ANTONII [103]

Answer:

E_{T} = 36.84 J        

Step-by-step explanation:

La energía mecánica total está dada por:

E_{T} = E_{c} + E_{p}

E_{T} = \frac{1}{2}mv^{2} + mgh

En donde:

m: es la masa = 150 g

v: es la velocidad = 0.8 m/s

h: es la altura = 25 m

g: es la gravedad = 9.81 m/s²

E_{T} = \frac{1}{2}mv^{2} + mgh = \frac{1}{2}0.15 kg*(0.8 m/s)^{2} + 0.15 kg*9.81 m/s^{2}*25 m = 36.84 J

Por lo tanto, la energía mecánica total es 36.84 J.

Espero que te sea de utilidad!      

5 0
3 years ago
Find the isosceles triangle side lengths
garik1379 [7]
You haven't included a diagram, however, if it's an isosceles triangle 2 of its sides will be the same and 1 will be different
7 0
2 years ago
Read 2 more answers
PLEASE HELP VERY IMPORTANT I REALLY NEEDS HELP
strojnjashka [21]
[see picture link]Area of part 1:A1=base*height/2=(8+2)*(8-2-2-1)/2=10*3/2=15 ft^2Area of part 2:A2=length*width=(8+2)*1=10 ft2Area of part 3:A3=length*width=8*2=16 ft2
Picture: https://us-static.z-dn.net/files/d30/9033549987fa60cf57fe05f71424f322.gif
6 0
3 years ago
PLZ HELP PLZ HELP
ankoles [38]

Answer:

c

Step-by-step explanation:

3 0
2 years ago
Can you please help me with this one
My name is Ann [436]

Answer:

6x=-60

Step-by-step explanation:

3 0
2 years ago
Other questions:
  • Write a word problem that can be solved by using 2×5÷5
    10·2 answers
  • Which of the following inequalities are true? Select all of the correct
    13·1 answer
  • Write the equation of the line that has the slope m=2/5 and passes through the point ​(25​,−9​). Write the equation in​ slope-in
    9·1 answer
  • Write a related addition fact for 15-6 = 9
    13·2 answers
  • Someone explain this equation plz
    8·1 answer
  • Farmer Janet can plant 9 feet of carrots in 15 minutes while her daughter Amy can plant 17 feet of carrots in half an hour. Whic
    11·1 answer
  • Helpppp plssssss I need to get my grade up in math
    13·1 answer
  • Dave's favorite baseball team has won 10 fewer games than Kimiko's favorite baseball team. Write an algebraic expression for the
    5·1 answer
  • - 3 7/9 - 1 2/9 <br> What is this answer
    11·2 answers
  • 5. A farmer has 100 m of wire fencing. What area can she enclose if
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!