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
mixas84 [53]
3 years ago
6

Find the height of a cylinder with a surface area of 108 pi square meters. The radius of the cylinder is twice the height.

Mathematics
1 answer:
myrzilka [38]3 years ago
4 0
Let
x---------> radius of the cylinder
y---------> the height of the cylinder

we know that
x=2y
[surface area of cylinder]=2*[pi*r²]+2*pi*r*h
surface area=108*pi m²
r=x
h=y
x=2y
108*pi=2*[pi*(2y)²]+2*pi*(2y)*y
108*pi=8*pi*y²+4*pi*y²
108*pi=12*pi*y²
y²=108/12
y²=9----------> y=√9--------> y=3 m
x=2y-------> x=2*3-----> x=6 m

the answer is
the height of the cylinder is 3 m
You might be interested in
What is 7 and one fifth divided by 8? Plz help
USPshnik [31]
7 \frac{1}{5} \div 8= 4/5
8 0
3 years ago
Mr. Cole is putting hardwood flooring in the area of his house shown at the Wright. He is also putting crown molding around the
Leokris [45]

Answer:

are there any numbers?

Step-by-step explanation:

6 0
2 years ago
A juggler tosses a ball into the air . The balls height, h and time t seconds can be represented by the equation h(t)= -16t^2+40
malfutka [58]
PART A

The given equation is

h(t) = - 16 {t}^{2} + 40t + 4

In order to find the maximum height, we write the function in the vertex form.

We factor -16 out of the first two terms to get,

h(t) = - 16 ({t}^{2} - \frac{5}{2} t) + 4

We add and subtract

- 16(- \frac{5}{4} )^{2}

to get,

h(t) = - 16 ({t}^{2} - \frac{5}{2} t) + - 16( - \frac{5}{4})^{2} - -16( - \frac{5}{4})^{2} + 4

We again factor -16 out of the first two terms to get,

h(t) = - 16 ({t}^{2} - \frac{5}{2} t + ( - \frac{5}{4})^{2} ) - -16( - \frac{5}{4})^{2} + 4

This implies that,

h(t) = - 16 ({t}^{2} - \frac{5}{2} t + ( - \frac{5}{4}) ^{2} ) + 16( \frac{25}{16}) + 4

The quadratic trinomial above is a perfect square.

h(t) = - 16 ( t- \frac{5}{4}) ^{2} +25+ 4

This finally simplifies to,

h(t) = - 16 ( t- \frac{5}{4}) ^{2} +29

The vertex of this function is

V( \frac{5}{4} ,29)

The y-value of the vertex is the maximum value.

Therefore the maximum value is,

29

PART B

When the ball hits the ground,

h(t) = 0

This implies that,

- 16 ( t- \frac{5}{4}) ^{2} +29 = 0

We add -29 to both sides to get,

- 16 ( t- \frac{5}{4}) ^{2} = - 29

This implies that,

( t- \frac{5}{4}) ^{2} = \frac{29}{16}

t- \frac{5}{4} = \pm \sqrt{ \frac{29}{16} }

t = \frac{5}{4} \pm \frac{ \sqrt{29} }{4}

t = \frac{ 5 + \sqrt{29} }{4} = 2.60

or

t = \frac{ 5 - \sqrt{29} }{4} = - 0.10

Since time cannot be negative, we discard the negative value and pick,

t = 2.60s
8 0
3 years ago
Graph the function f(x) = -1/4 x - 2 <br><br>just tell me the points
cupoosta [38]
Two points are (0,-2) and (400,-102).
8 0
3 years ago
Students are comparing their heights jose is 4 1/6 feet tall lee is 4 1/4 feet tall judi is 4 1/12 feet tall and sammy is 4 2/3
klemol [59]
Sammy is the tallest one because he is 4.667 feet tall
6 0
3 years ago
Read 2 more answers
Other questions:
  • Whats the answer for <br> b.b 9=21?
    9·1 answer
  • What is spqure root and how do i use it?<br><br>are they any math apps or for Android?
    14·1 answer
  • What is 3 1/4 - 3 1/9
    13·1 answer
  • Write 3.666 as a fraction
    6·2 answers
  • Please help me, I would gladly appreciate it. :)
    7·1 answer
  • Find the area.
    15·1 answer
  • F(x) = 2/3 |x-4| need help on homework
    5·1 answer
  • Sarah makes 5 ribbons the first day. On the second day she doubles the number of
    11·2 answers
  • Question
    7·1 answer
  • Simone saved $15.45 from allowance, had $7.37 in her piggy bank, and had $22.55 left from her birthday. How much money does Simo
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!