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
Alik [6]
3 years ago
8

a train leaves little rock, arkansas and travels north at 70 kilometers per hour. another train leaves at the same time and trav

els south at 80 kilometers per hour. how long will it take before they are at 450 kilometers apart
Mathematics
1 answer:
jekas [21]3 years ago
8 0
45 hours.
80 - 70= 10, and 450/10 is 45.
to justify, you can do 70x45= 3,150, and 80x45= (3,600 - 3,150= 450)
You might be interested in
Rewrite the formula to find the width of the base of the prism if the volume, length of the base, and height of the prism are al
notsponge [240]

Answer:

w = V/lh

Step-by-step explanation:

The volume of a rectangular prism is calculated using the formula V = lwh, where V is the volume of the prism, l and w are the length and width of the base of the prism, respectively, and h is the height of the prism.

Rewrite the formula to find the width of the base of the prism if the volume, length of the base, and height of the prism are already known.

volume of a rectangular prism,V = lwh

Where,

l = length of the base of the prism

w = width of the base of the prism

h = height of the prism

Rewrite the formula to find w

V = lwh

w = V/lh

That is,

width of the base of the prism = volume of the prism divided by length of the base of the prism multiplied by height of the prism

5 0
3 years ago
Find the solution of the given initial value problem:<br><br> y''- y = 0, y(0) = 2, y'(0) = -1/2
igor_vitrenko [27]

Answer:  The required solution of the given IVP is

y(x)=\dfrac{3}{4}e^x+\dfrac{5}{4}e^{-x}.

Step-by-step explanation:  We are given to find the solution of the following initial value problem :

y^{\prime\prime}-y=0,~~~y(0)=2,~~y^\prime(0)=-\dfrac{1}{2}.

Let y=e^{mx} be an auxiliary solution of the given differential equation.

Then, we have

y^\prime=me^{mx},~~~~~y^{\prime\prime}=m^2e^{mx}.

Substituting these values in the given differential equation, we have

m^2e^{mx}-e^{mx}=0\\\\\Rightarrow (m^2-1)e^{mx}=0\\\\\Rightarrow m^2-1=0~~~~~~~~~~~~~~~~~~~~~~~~~~[\textup{since }e^{mx}\neq0]\\\\\Rightarrow m^2=1\\\\\Rightarrow m=\pm1.

So, the general solution of the given equation is

y(x)=Ae^x+Be^{-x}, where A and B are constants.

This gives, after differentiating with respect to x that

y^\prime(x)=Ae^x-Be^{-x}.

The given conditions implies that

y(0)=2\\\\\Rightarrow A+B=2~~~~~~~~~~~~~~~~~~~~~~~~~~~(i)

and

y^\prime(0)=-\dfrac{1}{2}\\\\\\\Rightarrow A-B=-\dfrac{1}{2}~~~~~~~~~~~~~~~~~~~~~~~~(ii)

Adding equations (i) and (ii), we get

2A=2-\dfrac{1}{2}\\\\\\\Rightarrow 2A=\dfrac{3}{2}\\\\\\\Rightarrow A=\dfrac{3}{4}.

From equation (i), we get

\dfrac{3}{4}+B=2\\\\\\\Rightarrow B=2-\dfrac{3}{4}\\\\\\\Rightarrow B=\dfrac{5}{4}.

Substituting the values of A and B in the general solution, we get

y(x)=\dfrac{3}{4}e^x+\dfrac{5}{4}e^{-x}.

Thus, the required solution of the given IVP is

y(x)=\dfrac{3}{4}e^x+\dfrac{5}{4}e^{-x}.

4 0
3 years ago
A pet store had three hundred thirteen siamese cats and fifty-six house cats. During a sale the sold ninety-four cats. How many
laiz [17]

Answer:

275

Step-by-step explanation:

313 + 56= 369

369- 94= 275

6 0
3 years ago
Read 2 more answers
Solve the equation for x 1/3x - 15 = 12
Akimi4 [234]
X = 81
You are welcome
6 0
3 years ago
Read 2 more answers
If David and jake each looked at a strand of their hair under a microscope measured the diameter jake strand was 0.005 cm in the
Mama L [17]

Answer:

<h2>Jake's strand represents 4 times David's strand.</h2>

Step-by-step explanation:

To find the ratio between these diameters, we just need to divide them

k=0.005cm and d=0.0012cm

If we divide

\frac{k}{d}=\frac{0.005}{0.0012} \approx 4

Therefore, Jake's strand represents 4 times David's strand.

3 0
3 years ago
Read 2 more answers
Other questions:
  • Which table shows a proportional relationship?
    12·1 answer
  • A cyclist rides his bike at a rate of
    5·1 answer
  • What is the missing piece of the information in the paragraph proof?
    9·2 answers
  • What are the solutions to 6x^2-5x-4=0?​
    5·1 answer
  • A self-serve frozen yogurt store made these graphs to study the data collected about its customers' purchases. Which statement i
    8·1 answer
  • The scale factor of the blueprint of a front door to the actual front door is 0.04. The area of the actual front door is 36 ft2
    12·1 answer
  • WILL GIVE BRAINLST <br> ANSWER PLSS
    6·1 answer
  • The line segment between (9,6) and (-2,-1) is bisected at (3.5,2.5). Find the y-intercept of the perpendicular bisector.
    15·1 answer
  • What does 1/4 of a can of coffee cost if 4 cans of coffee cost $2. 40?.
    6·1 answer
  • What is the solution to the equation below?
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!