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Nate answered: 3498 problems
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Divisibility_and_Prime_Numbers/38396: How do you change 28/9 to a mixed or whole number.
1 solutions

Answer 23884 by Nate(3500) About Me  on 2006-05-18 12:38:14 (Show Source):
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28/9 original
3 and 1/9 .... how many times does nine go into 28 or a lower number
3 * 9 = 27 so 28-27=1
so: 31%2F9


Miscellaneous_Word_Problems/38338: This question is from textbook algebra
5. a bus went 318 km. farther than a car. the car went 1/3 as far as the bus. How far did each vechicle travel? choices for the car's distance: 147,151,159.
6.A clown weighs 60 lbs. more than a trapeeze artist.the trapeeze artist weighs 2/3 as mus as the clown. How much did each weigh? choices for the trapeeze artist:110,120,125.

thank you :]
1 solutions

Answer 23820 by Nate(3500) About Me  on 2006-05-17 22:51:07 (Show Source):
You can put this solution on YOUR website!
5. a bus went 318 km. farther than a car. the car went 1/3 as far as the bus. How far did each vechicle travel? choices for the car's distance: 147,151,159.
If you plug in the numbers, the car's distance went 159 km.
6.A clown weighs 60 lbs. more than a trapeeze artist.the trapeeze artist weighs 2/3 as mus as the clown. How much did each weigh? choices for the trapeeze artist:110,120,125.
If you plug in the numbers, the trapeeze weighs 120 lbs.


Quadratic-relations-and-conic-sections/38337: What are the foci of the ellipse with equation (x^2/100)+(y^2/64)=1
a.(0,+or- sqroot of 164)
b.(+or- sqroot of 164,0)
c.(0,+or- 6)
b.(+or- 6,0)
i got b in part guess mode ^_^
1 solutions

Answer 23817 by Nate(3500) About Me  on 2006-05-17 22:41:57 (Show Source):
You can put this solution on YOUR website!
(x^2/100)+(y^2/64)=1
The ellipse has a horizontal major axis with a center at (0,0).
a=10
b=8
c^2=a^2-b^2
c^2=100-64
c=6
Foci: (6,0),(-6,0)
Well, you are right. It is the second 'b'!


Points-lines-and-rays/38320: What is the area of s trapezoid with vertices(-3,-1), (3,3), (-1,3) and (3,-1)?
a.24 square units
b.20 square units
c16 square units
d.12 square units
1 solutions

Answer 23813 by Nate(3500) About Me  on 2006-05-17 22:36:53 (Show Source):
You can put this solution on YOUR website!
By using the distance formula, you get the two bases as 6 and 4 units long. Also, you get the width as 4 units long.
The formula for a trapezoid is: A=.5(b+b)(w) where 'b' are the bases and 'w' is the width
A=.5(10)(4)=20
The answer is (b.).


Polynomials-and-rational-expressions/38333: solve equation by factoring: (y-3)(y+2)= 0
1 solutions

Answer 23812 by Nate(3500) About Me  on 2006-05-17 22:27:16 (Show Source):
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(y-3)(y+2)= 0 It is factored! So, use the zero product property.
y-3=0 or y=3
y+2=0 or y=-2


Quadratic-relations-and-conic-sections/38335: find the equation for the parabola with focus (1,4) and directrix x=-3
1 solutions

Answer 23811 by Nate(3500) About Me  on 2006-05-17 22:26:04 (Show Source):
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the point in the middle of the focus and the dirextrix (the vertex) is (1,.5)
where p is 3.5 and the equation is p=1/4a
so 3.5=1/4a
ao a=1/14
standard form: y=a%28x-h%29%5E2%2Bk
y=%281%2F14%29%28x-1%29%5E2%2B.5


Rational-functions/37011: i have this problem but it's not in the book...
Find what the minimum surface area for a cylindrical can will be to hold 500cm%5E3. Give the radius and height.

Surface+area=2%28pi%29r%5E2h
volume=+%28pi%29r%5E2
1 solutions

Answer 23809 by Nate(3500) About Me  on 2006-05-17 22:19:57 (Show Source):
You can put this solution on YOUR website!
300+=+%28pi%29r%5E2
%28300%2F%28pi%29%29%5E%281%2F2%29+=+r
........................................................
Surface+area=2%28pi%29%28%28300%2F%28pi%29%29%5E%281%2F2%29%29%5E2h
Surface+area=2%28pi%29%28300%2F%28pi%29%29h
Surface+area=600h
Surface area depends on height. If the height can only be integers greater than zero, then the minimum surface area is 600cm when the height is 1cm.


Quadratic-relations-and-conic-sections/38322: find the foci of the ellipse with equation x²/16+y²/25=1
1 solutions

Answer 23807 by Nate(3500) About Me  on 2006-05-17 22:10:52 (Show Source):
You can put this solution on YOUR website!
find the foci of the ellipse with equation x²/16+y²/25=1
vertical major axis
center(0,0)
a=5
b=4
c^2=a^2-b^2
c^2=25-16
c^2=9
c=3
Foci: (0,3),(0,-3)


Quadratic-relations-and-conic-sections/38331: what is the foci of the hyperbola with the equation y²/144-x²/100=1
1 solutions

Answer 23806 by Nate(3500) About Me  on 2006-05-17 22:08:31 (Show Source):
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find the foci of the hyperbola with equation y²/144-x²/100=1
vertical transverse axis
center(0,0)
a=12
b=10
c^2=a^2+b^2
c^2=144+100
c^2=244
c=(244)^(1/2)=4(61)^(1/2)
Foci: (0,4(61)^(1/2)),(0,-4(61)^(1/2))


Quadratic-relations-and-conic-sections/38323: find the foci of the hyperbola with equation y²/144-x²/100=1
1 solutions

Answer 23805 by Nate(3500) About Me  on 2006-05-17 22:07:36 (Show Source):
You can put this solution on YOUR website!
find the foci of the hyperbola with equation y²/144-x²/100=1
vertical transverse axis
center(0,0)
a=12
b=10
c^2=a^2+b^2
c^2=144+100
c^2=244
c=(244)^(1/2)=4(61)^(1/2)
Foci: (0,4(61)^(1/2)),(0,-4(61)^(1/2))


Graphs/38324: if n=4.97,solve for 31.6-n
1 solutions

Answer 23804 by Nate(3500) About Me  on 2006-05-17 22:02:54 (Show Source):
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if n=4.97,solve for 31.6-n
31.6-4.97=26.63


Quadratic-relations-and-conic-sections/38329: what is the foci of the ellipse with the equation x²/16+y²/25=1
1 solutions

Answer 23803 by Nate(3500) About Me  on 2006-05-17 22:01:24 (Show Source):
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x%5E2%2F16%2By%5E2%2F25=1
center(0,0)
vertical major axis
a=5
b=4
c^2=a^2-b^2
c^2=25-16
c^2=9
c=3
foci: (0,3),(0,-3)


Quadratic-relations-and-conic-sections/38316: Classify the following as parabolas, ellipses, hyperbolas or circles.
x²+y²-10x+9=0
4y²+9=x
6x²+10y²=60
1 solutions

Answer 23802 by Nate(3500) About Me  on 2006-05-17 21:17:28 (Show Source):
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x²+y²-10x+9=0 is a circle
4y²+9=x is a parabola
6x²+10y²=60 is an ellipse


Quadratic_Equations/38318: A golf ball is hit into the air. The path of the ball can be described by the equation h=70t-5t(squared) where h is the height of the ball in meters and t is the time in seconds.
A. how high is the ball after 3 seconds
B. after how many seconds will the ball be 169 meters high
C. when will the ball hit the ground?
~Thanx,
Steve
1 solutions

Answer 23801 by Nate(3500) About Me  on 2006-05-17 21:15:10 (Show Source):
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A. how high is the ball after 3 seconds
h=70%283%29-5%283%29%5E2
h=210-45
h=165
B. after how many seconds will the ball be 169 meters high
169=70%28t%29-5%28t%29%5E2
-5%28t%29%5E2%2B70t-169=0
't' is either %28-70+%2B+%281520%29%5E%281%2F2%29%29%2F%28-10%29%29 or %28-70+-+%281520%29%5E%281%2F2%29%29%2F%28-10%29%29
The answer is %28-70+-+%281520%29%5E%281%2F2%29%29%2F%28-10%29%29 because you can not have a negative time. The answer is about 10.8987
C. when will the ball hit the ground?
0=70%28t%29-5%28t%29%5E2
0=t%2870-5t%29
set to zero (use product property)
t=0
70-5t=0
-5t=-70
t=14
The ball will hit the ground after 14 seconds.


Human-and-algebraic-language/38315: Can a tutor please tell me this question in an equation: A truck traveling at a constant rate of 45 mph leaves Albany. One hour later a car traveling at a constant rate of 60 mph also leaves Albany traveling in the same direction on the same highway. How long will it take for the car to catch up to the truck, if bobth vehicles continue in the same direction on the highway.
We learned this at the beginning of the year, so I really can't remember, and my notes don't seem to have any problems with the hour difference in it. I attempted to make a graph, but it came out wrong, once again because I'm not sure how to put the hour difference in.
1 solutions

Answer 23799 by Nate(3500) About Me  on 2006-05-17 21:04:43 (Show Source):
You can put this solution on YOUR website!
Choose the equations:
y=45x
and
y=60x-45
where y is the distance and x is the hours (also, subtract 45 in the second equation due to the truck had already one hour (45 miles) traveled)
Combine to get: x=3 So they will meet at three hours.


Linear-equations/38314: please help me on this slope question, what is the slope of (-1,4),(5,2)
1 solutions

Answer 23798 by Nate(3500) About Me  on 2006-05-17 20:56:09 (Show Source):
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slope = (y-y)/(x-x}
slope = (2-4)/(5-(-1))
slope = (-2)/(6)
slope = (-1/3)


Quadratic-relations-and-conic-sections/38304: Find the slopes of the assymptotes of the hyperbola with equation x²/64 - y²/36=1
1 solutions

Answer 23793 by Nate(3500) About Me  on 2006-05-17 20:49:02 (Show Source):
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Find the slopes of the assymptotes of the hyperbola with equation x%5E2%2F64+-+y%5E2%2F36=1
The hyperbola is horizontal, so the slope is b/a ....
a=8
b=6
and the center point is (0,0)
Use point-slope form: y+-+yp+=+m%28x+-+xp%29 where yp and xp are points
y+-+0+=+%286%2F8%29%28x+-+0%29 and y+-+0+=+%28-6%2F8%29%28x+-+0%29
y+=+%283%2F4%29x and y+=+-%283%2F4%29x


Polynomials-and-rational-expressions/38308: How do you find the leasr common multiple of
20x to the 5 power and y to the 2
1 solutions

Answer 23791 by Nate(3500) About Me  on 2006-05-17 20:43:09 (Show Source):
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How do you find the leasr common multiple of
20x to the 5 power and y to the 2
(20x)(20x)(20x)(20x)(20x) and (y)(y)
first, look at %2820x%29%5E5
What does this term miss that y%5E2 has?
It is missing two y's of course!
So: %2820x%29%5E5%28y%29%5E2


Exponential-and-logarithmic-functions/38297: The population of a small town of 10,000 people is growing at the rate of about 5.2% per year. Predict the approximate population after n years.
1 solutions

Answer 23789 by Nate(3500) About Me  on 2006-05-17 20:40:42 (Show Source):
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P%28a%29+=+a%281%2Br%29%5En where P(a) is the final amount, 'a' is the initial amount, and 'r' is the rate
P%28a%29+=+10000%281%2B.052%29%5En
P%28a%29+=+10000%281.052%29%5En


Systems-of-equations/38309: We have threee adults who have collectively have math degress, MBA and a 12 year old with a problem that none of us came arrive at the equation. It reads as folows:
The difference of a number from 8 is 3 more than the product of the same number and five.
This is a bit of an embarassment as I am visiting my nephew and he is having fun watching us try to dome with this answer.
Hope you can help.
Thanks
Deborah Linsley
1 solutions

Answer 23788 by Nate(3500) About Me  on 2006-05-17 20:38:58 (Show Source):
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The difference of a number from 8 is 3 more than the product of the same number and five.
Define the number as 'x' ....
8-x=5x%2B3
-6x=-5
x=%285%2F6%29
Your number is (5/6).


Miscellaneous_Word_Problems/38305: A vending machine has $41.25 in it. There are 225 coins total and the machine only accepts nickels, dimes , and quarters. There are twice as many dimes as nickels. How many of each coin are in the machine?
1 solutions

Answer 23786 by Nate(3500) About Me  on 2006-05-17 20:26:22 (Show Source):
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A vending machine has $41.25 in it. There are 225 coins total and the machine only accepts nickels, dimes , and quarters. There are twice as many dimes as nickels. How many of each coin are in the machine?
Variables:
d=number of dimes
n=number of nickels
q=number of quarters
Equations:
.1d%2B.05n%2B.25q=41.25
d%2Bn%2Bq=225
d=2n
Combine:
-.1d-.1n-.1q=-22.5
+
.1d%2B.05n%2B.25q=41.25
=
-.05n%2B.15q=18.75
and
-d-n-q=-225
+
d-2n=0
=
-3n-q=-225
Combine:
3n-9q=-1125
+
-3n-q=-225
=
-10q=-1350
q=135
Combine:
-3n-q=-225
-3n-135=-225
-3n=-90
n=30
combine:
d%2B30%2B135=225
d%2B165=225
d=60
So there are 60 dimes, 30 nickels, and 135 quarters.


Miscellaneous_Word_Problems/38306: The length of a rectangle is decreased by three feet, and the width is increased by one foot, forming a square region having an area of 25 square feet. What is the area of th original rectangular region?
1 solutions

Answer 23785 by Nate(3500) About Me  on 2006-05-17 20:16:09 (Show Source):
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If the square's area is 25 squared feet, then each side is 5 feet.
Length=5+3=8 feet
Width=5-1=4 feet


Rational-functions/38301: Find the zeros of the function f(x)=2x4-x³+3x²-3x-9
Note please that where it says 2x4 it's actually supposed to be 2x to the fourth power. Thank You.
1 solutions

Answer 23784 by Nate(3500) About Me  on 2006-05-17 20:13:37 (Show Source):
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Find the zeros of the function f%28x%29=2x%5E4-x%5E3%2B3x%5E2-3x-9
For short, I will use synthetic division and Descarte's Rule of Signs.
f%28x%29=%28%28x-%283%2F2%29%29%28x%2B1%29%282x%5E2%2B6%29%29
Zeros should be: 1.5, -1, +-i(3)^(1/2)


Permutations/38302: Divide
A. Use long division to divide x³+6x²-x-30 by x²+8x+15

B. Use synthetic division to divide (x³+5x²-18)/(x+3)
1 solutions

Answer 23783 by Nate(3500) About Me  on 2006-05-17 20:03:41 (Show Source):
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A. Use long division to divide x³+6x²-x-30 by x²+8x+15
%28x%5E3%2B6x%5E2-x-30%29%2F%28x%5E2%2B8x%2B15%29
%28%28x%2B3%29%28x%2B5%29%28x-2%29%29%2F%28%28x%2B3%29%28x%2B5%29%29
x-2
B. Use synthetic division to divide (x³+5x²-18)/(x+3)
x....1....5....0....-18
-3 ! 1 ! 2 ! -6 ! 0
So: x%5E2+%2B+2x+-6


Trigonometry-basics/38303: please please help me with this problem.ive tried and tried and i still cant get the answer. If the latitude of Chicago is about 42degrees and the radius of the earth is about 4000 miles, how far is Chicago from the equator?(use pi=3.1416)
1 solutions

Answer 23782 by Nate(3500) About Me  on 2006-05-17 19:55:50 (Show Source):
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You need to know the distance of the circumference:
C=%28pi%29r%5E2
C=%283.1416%29%284000%29%5E2
C=50265600
Know, we know that 360 degrees is equal to a circle, so 42/360 is to be used.
(42/360)(C)=distance
The distance should be 5,864,320 miles.


Graphs/38287: dear online tutor,
i'm having trouble graphing problems such as y=2x-5 and problems like y<2x+1. can you help me or at least give me some examples

1 solutions

Answer 23780 by Nate(3500) About Me  on 2006-05-17 19:49:00 (Show Source):
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y=2x-5
Use slope-intercept form y=mx%2Bb where m is the slope and b is the y-intercept
graph the point (-5) on the y-axis .... then, go 2 units up and 1 to the right (use the slope: 2/1) or you go two units down and one unit to the left (use the slope: (-2)/(-1))

for y<2x+1 .... graph the line as dotted and shade beneath the line (hence, < means less than)


Quadratic-relations-and-conic-sections/38295: name the vertex for the parabola with equation y=3x²-12x+16
1 solutions

Answer 23779 by Nate(3500) About Me  on 2006-05-17 19:43:55 (Show Source):
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y=3x%5E2-12x%2B16 original
y-16=3x%5E2-12x add constant
%28y%2F3%29-%2816%2F3%29=x%5E2-4x divide by three
%28y%2F3%29-%2816%2F3%29%2B%2812%2F3%29=%28x-2%29%5E2 complete the square
%28y%2F3%29-%284%2F3%29=%28x-2%29%5E2 combine
%28y%2F3%29=%28x-2%29%5E2%2B%284%2F3%29 add
y=3%28x-2%29%5E2%2B4 multiply by three
Use stantard form y=a%28x-h%29%5E2%2Bk where the vertex is (h,k).
Vertex is (2,4).


Quadratic_Equations/38233: Find the nth term formula for the geometric sequence whose first term is 4 and whose common ratio is -3.

1 solutions

Answer 23712 by Nate(3500) About Me  on 2006-05-17 14:08:30 (Show Source):
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P+=+a%2Ar%5E%28n-1%29 where P is the nth term and 'a' is the first term
P+=+4%2A%28-3%29%5E%28n-1%29


Quadratic-relations-and-conic-sections/38222: standard form of parabola vertex (0,0) and focus (0,5)
and
equation of ellipse vertex (-8,0), co-vertex (0,4) center (0,0)

1 solutions

Answer 23711 by Nate(3500) About Me  on 2006-05-17 13:45:17 (Show Source):
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standard form of parabola vertex (0,0) and focus (0,5)
'p' is the distance from the vertex to the focus and is equal to 1/(4a)
p=5 .... so
5 = 1/(4a)
20a = 1
a = (1/20)
standard form: y+=+a%28x+-+h%29%5E2+%2B+k where (h,k) is the vertex
y+=+%281%2F20%29%28x%29%5E2
equation of ellipse vertex (-8,0), co-vertex (0,4) center (0,0)
a=8
b=4
standard form: %28%28%28x+-+h%29%5E2%29%2Fa%5E2%29%2B%28%28y+-+k%29%5E2%2Fb%5E2%29=1 where the center is (h,k)
%28%28%28x%29%5E2%29%2F64%29%2B%28%28y%29%5E2%2F16%29=1


Divisibility_and_Prime_Numbers/38225: Evette has 41 1/2 ft. of string. She wants to cut it into pieces 3 3/4 ft. long. How many pieces of string will she have? How much string remains, if any?
Thanks!
1 solutions

Answer 23710 by Nate(3500) About Me  on 2006-05-17 13:38:24 (Show Source):
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41.5%2F3.75
11 and 0.25 of the string will be left over


Exponential-and-logarithmic-functions/38155: Please help I am stuck on this one,
Most calculators have 2 different logs on them: log, which is base 10, and ln, which is base e. In computer science, digital computers are based on the binary numbering system which means that there are only 2 numbers available to the computer, 0 and 1. When a computer scientist needs a logarithm, he needs a log to base 2 which is not on any calculator. To find the log of a number to any base, we can use a conversion formula as shown here:
log ^ (b)a =log a/log b

Using this formula, find log ^ (2) 1000 .

1 solutions

Answer 23637 by Nate(3500) About Me  on 2006-05-16 21:01:16 (Show Source):