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15390..15419 , 15420..15449 , 15450..15479 , 15480..15509 , 15510..15539 , 15540..15569 , 15570..15599 , 15600..15629 , 15630..15659, >>NextVolume/599102: A cylindrical container that holds tennis balls has diameter 3 inches and height of 12 inches. Each spherical tennis ball that holds has a radius 1.4 inches. How many tennis balls can the container hold?
1 solutions
Answer 378846 by ankor@dixie-net.com(15649)   on 2012-04-15 14:48:47 (Show Source):
You can put this solution on YOUR website!A cylindrical container that holds tennis balls has diameter 3 inches and height of 12 inches. Each spherical tennis ball that holds has a radius 1.4 inches. How many tennis balls can the container hold?
:
2*1.4 = 2.8" the diameter of the balls
 = 4.28 ~ 4 balls
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Travel_Word_Problems/599106: Ashley rides her bike every 8 days. Sam rides her bike every 12 days, and James rides his bike every 18 days. If they all ride their bikes today, in how many days will they all ride their bikes again on the same day?
1 solutions
Answer 378828 by ankor@dixie-net.com(15649) on 2012-04-15 13:37:38 (Show Source):
You can put this solution on YOUR website!Ashley rides her bike every 8 days. Sam rides her bike every 12 days, and James rides his bike every 18 days.
If they all ride their bikes today, in how many days will they all ride their bikes again on the same day?
:
This is a Least Common Multiple problem
:
Prime factor each
8: 2,2,2
12:2,2,3
18:2*3*3
Therefore
2*2*2*3*3 = 72 days
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Linear_Equations_And_Systems_Word_Problems/598934: the element decays at the rate of S(t)=se^-0.036t, where t is time in yrs and s the initial size in grams. If you have a 83-gram piece of this element how many grams will have in 2 yrs from now? round to nearest tenth of a gram.
1 solutions
Answer 378826 by ankor@dixie-net.com(15649) on 2012-04-15 13:21:55 (Show Source):
You can put this solution on YOUR website!the element decays at the rate of S(t)=se^-0.036t, where t is time in yrs and s the initial size in grams.
If you have a 83-gram piece of this element how many grams will have in 2 yrs from now? round to nearest tenth of a gram.
:
Find  with a calc
S(t) = 83 * .93053
S(t) = 77.2 gr after 2 yrs
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Graphs/598953: Plz help me with 3x + 4y = 4. I tried to isolate x by subtracting 4y from both sides but now I'm stuck (3x + 4y - 4y= 4- 4y). If you could please show me a step by step that would be so great.
THanks
Angela
1 solutions
Answer 378817 by ankor@dixie-net.com(15649) on 2012-04-15 12:36:15 (Show Source):
You can put this solution on YOUR website!3x + 4y = 4
I assume you are solving for x, subtract 4y from both sides, just like you did
3x = -4y + 4
divide both sides by 3
 =  + 
x =  y +
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Polynomials-and-rational-expressions/598986: I am only getting half of the equation right. I am not sure how the answer is coming up as an "m+1+ or "m-1" I am a complete math idiot, so I really need someone who can show me step by step, not just give me an answer, as this is my last class before applying to the nursing program, and I need to understand this for the final, not just be able to rely on finding the answer. I am literally the "ULTIMATE MATH RETARD" you will ever encounter. Thank you so much, in advance :)
4m^2-18m+14
15m^3+24m^2+9m
15m^2-10m-25
50m^3-2m
3m^2-10m+8
60m^3+54m^2-6m
1 solutions
Answer 378805 by ankor@dixie-net.com(15649) on 2012-04-15 11:22:28 (Show Source):
You can put this solution on YOUR website!Factor:
:
4m^2 -18m + 14
We can simplify this, factor out 2
2(2m^2 - 9m + 7)
Further factor this to
2(2m - 7)(m - 1)
Confirm this by FOILing (2m-7)(m-1), this will help you understand what we are doing here
:
15m^3 + 24m^2 + 9m
Simplify this by factoring out 3m
3m(5m^2 + 8m + 3)
Factor this to
3m(5m + 3)(m + 1)
Confirm this to yourself, FOIL (5m+3)(m+1)
:
15m^2 - 10m - 25
Factor out 5
5(3m^2 - 2m - 5)
Factors to
3(3m - 5)(m + 1)
FOIL this to confirm it
:
50m^3 - 2m
Simplify, factor out 2m
2m(25m^2 - 1)
we recognize this as the "difference of squares" factor to
2m(5m+1)(5m-1)
FOIL this, you can see that the middle terms will cancel each other out
:
3m^2 - 10m + 8
(3m - 4)(m - 2)
:
60m^3 + 54m^2 - 6m
Factor out 6m
6m(10m^2 + 9m - 1)
factor this to
6m(10m-1)(m+1)
Here again FOIL, this will help you get familiar with this. FOILing then reversing the process, see the the three terms each have an operation
If you do not know how to FOIL, you have a big problem, email me in the comment section, I will try to explain it. C
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Travel_Word_Problems/598981: Please help me solve this word problem:
If a biker and a walker both leave the same location at the same time and are both going to the same destination. The biker is traveling at 16 mph and the walker is traveling at 4 mph and the biker arrives 1 hour before the walker does. How long was the biker on the road, how long was the walker on the road, and what was the distance between where they started and where they stopped?
1 solutions
Answer 378797 by ankor@dixie-net.com(15649) on 2012-04-15 10:18:17 (Show Source):
You can put this solution on YOUR website!If a biker and a walker both leave the same location at the same time and are both going to the same destination.
The biker is traveling at 16 mph and the walker is traveling at 4 mph and the biker arrives 1 hour before the walker does.
How long was the biker on the road, how long was the walker on the road, and what was the distance between where they started and where they stopped?
:
Let t = time the biker was on the road
then
(t+1) = time the walker was
:
Write a distance equation, (both went the same distance)
16t = 4(t+1)
16t = 4t + 4
16t - 4t = 5
12t = 4
t = 4/12
t =  hr or 20 min, bike time
then obviously: 1 hrs, walk time
:
Find the distance
1/3 * 16 = 5.33 miles is the distance
:
We can confirm this by finding the walker distance
1.33 * 4 = 5.33 miles
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Miscellaneous_Word_Problems/598841: a group of students decided to purchase a tv ranging from 170 to 195 $. but at the last moment, two students backed out of the decision so that the remaining students had to pay 10 $. more than they had planned. find the cost of the tv if the amount has been shared equally among the students.
1 solutions
Answer 378738 by ankor@dixie-net.com(15649) on 2012-04-14 21:10:41 (Show Source):
You can put this solution on YOUR website!a group of students decided to purchase a tv ranging from 170 to 195 $.
but at the last moment, two students backed out of the decision so that the remaining students had to pay 10 $. more than they had planned.
find the cost of the tv if the amount has been shared equally among the students.
:
Let c = cost of the TV
Let s = original number of students
then
(s-2) = actual number of students that paid
:
 -  = 10
multiply by s(s-2), clear the denominators, results:
cs - c(s-2) = 10s(s-2)
cs - cs + 2c = 10s^2 - 20s
2c = 10s^2 - 20s
divide eq by 2
c = 5s^2 - 10s
We know that c has to be between 170 and 195
A little substitution for s reveals that only value for c is $175, when s=7 (original number students)
:
Check this actual number students are 5
175/5 = $35
175/7 = $25
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Polynomials-and-rational-expressions/598693: Help Please
1. Essay: Show all work. Find the following quotient:
64x^2 – 100 y^2
_______________
8x + 10y
2. Short Answer. The length of the side of a rectangular desk is given by 2x - 6y cm. The length of the front is given by 2x + 6y cm. What is an algebraic expression for the area of the top of the rectangular desk? Include correct units as part of your answer.
1 solutions
Answer 378707 by ankor@dixie-net.com(15649) on 2012-04-14 10:18:28 (Show Source):
You can put this solution on YOUR website!(64x^2–100x^2)/(8x+10y)
You should recognize the numerator as the "difference of squares"; can be factored to:
Cancel out (8x+10y) leaving
8x-10y
:
2. Short Answer. The length of the side of a rectangular desk is given by 2x - 6y cm. The length of the front is given by 2x + 6y cm. What is an algebraic expression for the area of the top of the rectangular desk? Include correct units as part of your answer.
:
A = L * W
A = (2x-6y)*(2x+6y)
FOIL
A = 4x^2 + 12xy - 12xy - 36y^2
A = 4x^2 - 36y^2 sq/cm
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Travel_Word_Problems/598568: a plane flying the 4258-mi trip from new york to london has a 50-mph tailwind. The flights point of no return is the point at which the flight time required to return to new york is the same as the time required to continue to london. if the speed of the plane in still air is 360 mph, how far is new york from the point of no return?
1 solutions
Answer 378695 by ankor@dixie-net.com(15649) on 2012-04-14 07:53:44 (Show Source):
You can put this solution on YOUR website!a plane flying the 4258-mi trip from new york to London has a 50-mph tailwind.
The flights point of no return is the point at which the flight time required to return to new york is the same as the time required to continue to London.
if the speed of the plane in still air is 360 mph, how far is new york from the point of no return?
:
Let d = distance from NY to point of no return
Then
(4258-d) = distance of that point from London
:
360 + 50 = 410 mph effective speed with the wind, (going east)
and
360 - 50 = 310 mph effective speed against the wind, (going west)
:
Time to return to NY = Time to continue to London
 = 
cross multiply
410d = 310(4258-d)
410d = 1319980 - 310d
310d + 410d = 1319980
720d = 1319980
d = 1319980/720
d = 1833 mi from New York
:
:
Check this by finding the flight times from d to London and from d back to NY
(4258-1833)/410 = 5.9 hrs
1859/310 = 5.9 hr
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Miscellaneous_Word_Problems/598559: The strontium-90 in a nuclear reactor decays continuously. If 200 mg is present initially, the amount present after t years is given by A(t)=200e^-0.0248t. Find, to nearest hundredth, the amount letft after 50 years.
I really could use some help with this word problem. I would greatly appreciate your help and I thank you.
1 solutions
Answer 378679 by ankor@dixie-net.com(15649) on 2012-04-13 21:14:10 (Show Source):
You can put this solution on YOUR website!The strontium-90 in a nuclear reactor decays continuously.
If 200 mg is present initially, the amount present after t years is given by A(t) = 200e^-0.0248t. Find, to nearest hundredth, the amount left after 50 years.
:
50 yrs means t = 50
A = 
:
A = 
A = 200 * .289384
A = 57.88 mg after 50 yrs
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Equations/598431: I NEED HELP PLEASE HELP :( 5)
-x+y=6
y=-7x+14
1 solutions
Answer 378659 by ankor@dixie-net.com(15649) on 2012-04-13 18:27:21 (Show Source):
You can put this solution on YOUR website!-x + y = 6
y = -7x + 14
:
Replace y in the 1st equation with (-7x+14), from the 2nd equation
-x + (-7x+14) = 6
-x - 7x = 6 - 14
-8x = -8
Divide both sides by -8, resulting in
x = 1
:
Find y using the 2nd equation replace x with 1
y = -7(1) + 14
y = -7 + 14
y = +7
:
Check solutions in the 1st equation replace x and y
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Travel_Word_Problems/598399: Corbin was driving his car at a speed of r miles per hour, when he had to stop suddenly. It took the car 254 feet to stop. The formula relating the distance d in feet required to stop to the speed r in miles per hour is d=0.05r(squared)+r. To the nearest mile per hour, how fast was Corbin traveling just before he braked?
1 solutions
Answer 378631 by ankor@dixie-net.com(15649) on 2012-04-13 12:45:30 (Show Source):
You can put this solution on YOUR website!Corbin was driving his car at a speed of r miles per hour, when he had to stop suddenly.
It took the car 254 feet to stop.
The formula relating the distance d in feet required to stop to the speed r in miles per hour is d=0.05r(squared)+r.
To the nearest mile per hour, how fast was Corbin traveling just before he braked?
:
d = 
d = 254, find r
= 254
A quadratic equation:
 = 0
Use the quadratic formula to find r
In this problem; x=r; a=.05; b=1; c= -254
Do the math and you should get a positive solution of:
r ~ 62 mph
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Travel_Word_Problems/598486: Eddie is flying a jet against the wind on a 330 mile trip. Flying with the same wind speed, Eddie could fly a 550 mile trip in the same amount of time. If Eddie's jet flies at 220 miles per hour in still air, what is the speed of the wind?
I have such a problem with algebra. I will appreciate any help you can give me.
Thank you,
Lynnette
1 solutions
Answer 378608 by ankor@dixie-net.com(15649) on 2012-04-13 09:53:55 (Show Source):
You can put this solution on YOUR website!Eddie is flying a jet against the wind on a 330 mile trip.
Flying with the same wind speed, Eddie could fly a 550 mile trip in the same amount of time.
If Eddie's jet flies at 220 miles per hour in still air, what is the speed of the wind?
:
Let w = the speed of the wind
then
(220-w) = his effective speed against the wind
and
(220+w) = his effective speed with the wind
:
Write a time equation; time = dist/speed
;
 = 
cross multiply
350(220+w) = 550(220-w)
77000 + 350s = 121000 - 550w
350w + 550w = 121000 - 77000
900w = 44000
w = 
w = 48.9 mph is the wind
:
:
We can confirm this by finding the times, they should be the same
550/(220+48.9) = 2.045 hrs
350/(220-48.9) = 2.045 hrs
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Percentage-and-ratio-word-problems/598478: Your elderly neighbour like to tell stories. In particular, he likes to tell the story of how he won the lottery when he was younger. Thing is, he can never quite remember the prize pool. He knows that he received $21,000 and that he contributed $2.00 to a $7.50 ticket. Can you help him figure out the total prize pool?
1 solutions
Answer 378605 by ankor@dixie-net.com(15649) on 2012-04-13 09:41:39 (Show Source):
You can put this solution on YOUR website!he received $21,000 and that he contributed $2.00 to a $7.50 ticket.
Can you help him figure out the total prize pool?
:
Let x = total prize
:
 x = 21000
multiply both sides by 7.5, results:
2x = 21000*7.5
2x = 157500
x = 157500/2
x = $78,750 total prize money
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Travel_Word_Problems/598021: a helicopter makes a round trip flight that lasts 4.5 hrs. if the average rate out was 80 miles per hour and the average rate in was 100 miles per hour. what was the helicopters greatest distance from the airport?
1 solutions
Answer 378552 by ankor@dixie-net.com(15649) on 2012-04-12 21:30:39 (Show Source):
You can put this solution on YOUR website!a helicopter makes a round trip flight that lasts 4.5 hrs.
if the average rate out was 80 miles per hour and the average rate in was 100 miles per hour.
what was the helicopters greatest distance from the airport?
:
Let d = the one-way trip
:
Write a time equation: time = dist/speed
:
time out + time back = 4.5 hrs
 +  = 4.5
Multiply by 400 to clear the denominators
400* + 400* = 400(4.5)
Cancel the denominators
5d + 4d = 1800
d = 1800/9
d = 200 miles max distance
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test/598261: 4^x - (17 times 2^x) + 16 = 0 (let me read it to make sure: 4 raised to the x power minus 17 times 2 raised to the x power plus 16 equals zero).
1 solutions
Answer 378550 by ankor@dixie-net.com(15649) on 2012-04-12 21:19:31 (Show Source):
You can put this solution on YOUR website! = 0
4 = 2 squared, therefore we can write it
 = 0
This looks like a quadratic equation where 2^x takes the place of x, factors to:
 = 0
Two solutions
2^x = 1
2^0 = 1
therefore
x = 0
and
2^x = 16
2^4 = 16
therefore
x = 4
:
Check this by replacing x with 4 in the original equation
 = 0
256 - 17(16) + 16 =
256 - 272 + 16 = 0
:
Do the same for x=0
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Linear_Equations_And_Systems_Word_Problems/598056: Together Fred, Sam, and Joe have $31. Use a system of equations to find the amount of money that Joe has if sam has $3 less than Fred and Joe has $1 more than Fred and Sam combined.
I need to know how you got the answer so please show the steps. Thanks!
1 solutions
Answer 378543 by ankor@dixie-net.com(15649) on 2012-04-12 21:01:33 (Show Source):
You can put this solution on YOUR website!Write an equation for each statement:
:
Together Fred, Sam, and Joe have $31.
f + s + j = 31
:
Use a system of equations to find the amount of money that Joe has if sam has $3
less than Fred
s = f - 3
:
and Joe has $1 more than Fred and Sam combined.
j = f + s + 1
j - f - s = 1
Add the 1st equation to the above equation
j - f - s = 1
j + f + s = 31
--------------- adding eliminates f and s
2j = 32
j = 32/2
j = $16 is Joe's amt
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Age_Word_Problems/598172: Bryan is twice as old as Colin. Colin is 4 years younger then Michael. In three years bryan Colin and Michael will be 2 more than half a century.how old are they now?
1 solutions
Answer 378541 by ankor@dixie-net.com(15649) on 2012-04-12 20:47:45 (Show Source):
You can put this solution on YOUR website!let b = Bryan's present age
let c = Colin's "
let m = Micheal's "
:
Write an equation for each statement:
:
"Bryan is twice as old as Colin."
b = 2c
:
"Colin is 4 years younger then Michael."
c = m - 4
or
m = c + 4
:
"In three years bryan Colin and Michael will be 2 more than half a century."
(b+3) + (c+3) + (m+3) = 52
b + c + m + 9 = 52
b + c + m = 52 - 9
b + c + m = 43
Replace b with 2c, replace m with (c+4)
2c + c + (c+4) = 43
4c = 43 - 4
4c = 39
c = 39/4
c = 9.75 yrs is Colin's present; usually expect an integer, but here it is
:
b = 2(9.75)
b = 19.5 yrs is Bryan's present age
:
m = 9.75 + 4
m = 13.75 yrs is Michael's present age
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Equations/597900: 23 - y = 53= I know you can subtract 23 from left side and have -y by itself. do you add 23 to the right side and now have -y =76. I know somehow you either multiply -y to both sides or divide both sides by -y or times it by -1. I can't remember. I do need to know when you subtract a number fron one side, you add it to the other side. Correct? How would you do this problem?
1 solutions
Answer 378481 by ankor@dixie-net.com(15649) on 2012-04-12 15:32:47 (Show Source):
You can put this solution on YOUR website!23 - y = 53
Remember, whatever you do to one side of the equation, you must do to the other side
In this equation subtract 23 from both sides
23 - 23 - y = 53 - 23
-y = 30
The variable (y) always has to be positive, multiply both sides by -1
-1 * -y = 30 * -1
y = -30
:
Check solution in original problem, replace with -30
23 - (-30) = 53
remember minus a minus is a plus
23 + 30 = 53, equality, so solution y=-30 is correct
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Equations/598032: It takes a passenger train 5hrs less time than it takes a freight train to make the trip from Ellettsville to Fairland. The passenger train averages 72km/h, while While freight train averages 36km/h.
Find the distance from Ellettsville to Fairland.
Please help.
1 solutions
Answer 378471 by ankor@dixie-net.com(15649) on 2012-04-12 14:26:07 (Show Source):
You can put this solution on YOUR website!It takes a passenger train 5hrs less time than it takes a freight train to make the trip from Ellettsville to Fairland.
The passenger train averages 72km/h, while freight train averages 36km/h.
Find the distance from Ellettsville to Fairland.
:
First find the times required
t = Pass train time
(t+5) = Freight time
:
Both trains went the same distance
Write a dist equation: dist = speed * time
72t = 36(t+5)
72t = 36t + 180
72t - 36t = 180
36t = 180
t = 5 hrs
:
Find the distance from E to F
5 * 72 = 360 mi
:
Check the distance, (freight time = 10 hrs)
10 * 36 = 360 mi
:
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Word_Problems_With_Coins/598095: You have had a tough time lately, bithdays, weddings,etc., and you now only have the money in your piggybank. You manage to shake out 16.00 dollars worth. You are suprised to see that you have the exact same amount of half dollars, quarters, dimes and nickels. How many of each do you have?
1 solutions
Answer 378470 by ankor@dixie-net.com(15649) on 2012-04-12 14:15:24 (Show Source):
You can put this solution on YOUR website!Total value $16.00
You have the exact same amount of half dollars, quarters, dimes and nickels.
How many of each do you have?
:
Let x = number of each coin
:
.05x + .10x + .25x + .50x = 16.00
.90x = 16
x = 16/.9
x = 17.77, not an integer, something not right with this problem
:
If the total was $18, there would be 20 of each coin.
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Exponential-and-logarithmic-functions/598044: Please help me solve f(x)= -2(3)^x +1 and how do u graph this? Thanks
1 solutions
Answer 378469 by ankor@dixie-net.com(15649) on 2012-04-12 13:33:09 (Show Source):
You can put this solution on YOUR website!f(x)= -2(3)^x +1
:
 = 0
 = -1
divide both sides by -2
 = 
:
= .5
using nat logs
x*ln(3) = ln(.5)
x = 
x = -.631
:
To graph this make a table of values starting with x=-2, the every half unit to x=+2
Using a calc:
y = -2(3^-2) + 1
y = -2(.111) + 1
y = .777
Find y for each value of x,
x | y
-------
-2.0|.78
-1.5|.62
-1.0|.33
-0.5|-.15
0.0 |-1.0
+0.5|-2.5
+1.0|-5
+1.5|-9.4
+2.0|-17
Your graph should look alot like this
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Money_Word_Problems/598047: $6000 is divided between two investments earning 7% and 9% simple interest. I want to earn a total annual of $500 interest. What is the smallest amount I can invest at 9% to earn the annual $500 interest?
1 solutions
Answer 378437 by ankor@dixie-net.com(15649) on 2012-04-12 09:02:16 (Show Source):
You can put this solution on YOUR website!$6000 is divided between two investments earning 7% and 9% simple interest.
I want to earn a total annual of $500 interest.
What is the smallest amount I can invest at 9% to earn the annual $500 interest?
:
Let x = amt invested at 9%
then
(6000-x) = amt invested at 7%
:
.07(6000-x) + .09x = 500
solve for x
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Trigonometry-basics/598015: Two factories blow their whistles at exactly the same time. If a man hears the two blasts exactly 2.5 seconds and 5.1 seconds after they are blown and the angle between his lines of sight to the two factories is 28.4 degrees, how far apart are the factories? Give your result to the nearest meter. ( use the fact that sound travels at 344 m/sec).
1 solutions
Answer 378436 by ankor@dixie-net.com(15649) on 2012-04-12 08:37:20 (Show Source):
You can put this solution on YOUR website!Two factories blow their whistles at exactly the same time.
If a man hears the two blasts exactly 2.5 seconds and 5.1 seconds after they are blown
and the angle between his lines of sight to the two factories is 28.4 degrees,
how far apart are the factories?
Give your result to the nearest meter. ( use the fact that sound travels at 344 m/sec).
:
Find the distances between the man and the factories
5.1 * 344 = 1754.4 m
2.5 * 344 = 860 m
:
The side opposite the angle of 28.4 degrees will be the distance between the factories.
A "side/angle/side" problem.
:
We can use the law of cosines
a^2 = b^2 + c^2 - 2bc*cos(A), where
a = distance between the factories
b = 1754.4
c = 860
A = 28.4 degrees
:
a^2 = 1754^2 + 860^2 - 2(1754.4*860)*cos(28.4)
After some tedious math, I got 1078.48 meter between the factories
See what you get.
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Linear_Equations_And_Systems_Word_Problems/597621: Word problem and having a hard time setting this up. I want to write it as, 40=x+(5+y) what am I doing and what should I be doing?
THanks
Admission to the zoo costs $5 more for an adult than for a child. Admission for two adults and two children costs $40. Find the cost of each adults admission and each childs admission.
1 solutions
Answer 378404 by ankor@dixie-net.com(15649) on 2012-04-11 21:33:11 (Show Source):
You can put this solution on YOUR website!Admission to the zoo costs $5 more for an adult than for a child.
Admission for two adults and two children costs $40.
Find the cost of each adults admission and each childs admission.
:
Let c = child's price of admission
then
(c+5) = adults price
:
2c + 2(c+5) = 40
2c + 2c + 10 = 40
4c = 40 - 10
4c = 30
c = 30/4
c = $7.50 for 1 child
then
7.50 + 5 = $12.50 for an adult
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