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Equations/531987: How do you solve for X? example: 17x – 42 = -39
1 solutions

Answer 350757 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 19:41:10 (Show Source):
You can put this solution on YOUR website!
we want to isolate x on one side by performing simple operations to both sides
17x - 42 = -39
add 42 to both sides
17x - 42 + 42 = -39 + 42
17x = +3
divide both sides by 17
17%2F17x = 3%2F17
x = 3%2F17
:
:
To check this in the original equation
17x - 42 = -39
replace x with 3/17
173%2F17 - 42 = -39
17's cancel, leaving
3 - 42 = -39
-39 = -39; equality, confirm our solution of x = 3/17


Rate-of-work-word-problems/531990: If a painter can paint a house in ½ a day and another painter can paint ¾ of
a house in two days, how many houses can they paint in a month? (30
days)
1 solutions

Answer 350751 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 19:33:40 (Show Source):
You can put this solution on YOUR website!
If a painter can paint a house in ½ a day and another painter can paint ¾ of
a house in two days, how many houses can they paint in a month? (30 days)
:
Painter 1: .5 house per day
Painter 2: 3%2F4*1%2F2 = 3%2F8 = .375 house per day
:
.5(30) + .375(30) =
15 + 11.25 = 26.25 houses in 30 days


Numbers_Word_Problems/531978: Find 3 consecutive numbers such that 4 times the first is equal to 7 more than the sum of the other two.
I do not understand how to work this problem. HELP!
1 solutions

Answer 350737 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 19:07:15 (Show Source):
You can put this solution on YOUR website!
Find 3 consecutive numbers such that 4 times the first is equal to 7 more than the sum of the other two.
:
3 numbers: x, (x+1), (x+2)
:
Write an equation for the statement:
"numbers such that 4 times the first is equal to 7 more than the sum of the other two. "
4x = (x+1) + (x+2) + 7
4x = 2x + 3 + 7
4x = 2x + 10
4x - 2x = 10
2x = 10
x = 5
:
The three numbers, 5, 6, 7
:
Check that in the given statement:
"3 consecutive numbers such that 4 times the first is equal to 7 more than the sum of the other two. "
4(5) = 6 + 7 + 7


Average/532053: The formula R = -0.075 + 3.85 can be used to predict the world record in the 1500 meter run, t years after 1930. Dertermine an inequality that identifies the years in which the world record will be < 3.7 minutes. t < ___ ? I have been bandging my head, and just cannot getthe formula, sorr to be so duh! Thanks...... have a good one
1 solutions

Answer 350676 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 16:44:51 (Show Source):
You can put this solution on YOUR website!
The formula R = -0.075 + 3.85 can be used to predict the world record in the 1500 meter run, t years after 1930. Determine an inequality that identifies the years in which the world record will be < 3.7 minutes. t < ___ ?
:
Assume the formula is:
R = -0.075t + 3.85
:
-.075t + 3.85 < 3.7 min
-.075t < 3.7 - 3.85
-.075t < -.15
t had to be positive, multiply both sides by -1, this reverses the inequality sign
.075t > .15
t > .15%2F.075
t > 2 yrs
Add that to 1930, we can say it will be less than 3.7 min after 1932
:
:
We can confirm that by finding the time in 1933 (t=3)
R = -0.075(3) + 3.85
R = -.225 + 3.85
R = 3.625 min, slightly less than 3.7
:
:
Hey! I have not heard that one before, does bandaging your head actually help?


Percentage-and-ratio-word-problems/532080: Ms. Niemeyer is taking the train 3,240 miles to Oregon. She will travel 1/8 the distance the first day and 1/6 the distance on the second day. How far will she have left to go after two days?
Please show me how to set up the equation.
S/
Parent
1 solutions

Answer 350669 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 16:30:04 (Show Source):
You can put this solution on YOUR website!
Ms. Niemeyer is taking the train 3,240 miles to Oregon.
She will travel 1/8 the distance the first day and 1/6 the distance on the second day.
How far will she have left to go after two days?
:
Let d = remaining distance after two days
:
d = 3240 - 1%2F8(3240) - 1%2F6(3240)
Both of these fraction will cancel into 3240, so you have
d = 3240 - 405 - 540
d = 2295 mi to go


Geometry_Word_Problems/531784: The volume of a rectangular box is 6 ft^3 more than twice the volume of a cube. The length of the box is 2 ft more than the length of an edge of the cube its width is equal to the length of an edge of the cube; and its height is 1 ft more than the length of an edge of the cube. What are the dimensions of the box and the cube?
1 solutions

Answer 350667 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 16:19:08 (Show Source):
You can put this solution on YOUR website!
The volume of a rectangular box is 6 ft^3 more than twice the volume of a cube. The length of the box is 2 ft more than the length of an edge of the cube its width is equal to the length of an edge of the cube; and its height is 1 ft more than the length of an edge of the cube. What are the dimensions of the box and the cube?
:
let x = the side of the cube
Write an equation for each statement:
"The volume of a rectangular box is 6 ft^3 more than twice the volume of a cube."
L * W * H = 2x^3 + 6
:
" The length of the box is 2 ft more than the length of an edge of the cube"
L = x + 2
:
"its width is equal to the length of an edge of the cube;"
W = x
:
"its height is 1 ft more than the length of an edge of the cube."
H = x + 1
:
Substituting for L,W,H
(x+2)*x*(x+1) = 2x^3 + 6
x(x^2 + x + 2x + 2) = 2x^3 + 6
x(x^2 + 3x + 2) = 2x^3 + 6
x^3 + 3x^2 + 2x = 2x^3 + 6
Combine like terms on the left
x^3 - 2x^3 + 3x^2 + 2x - 6 = 0
-x^3 + 3x^2 + 2x - 6 = 0
:
Graph this equation, there are two positive solutions but x=3 is an integer
+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+-x%5E3+%2B+3x%5E2+%2B+2x+-+6+%29+
:
What are the dimensions of the box and the cube?
x = 3 inches the side of the cube
then
L = 3+2 = 5 inches
W = 3 inches
H = 3+1 = 4 inches
:
:
Check this
5*3*4 = 2(3^3) + 6
60 = 2(27) + 6


Money_Word_Problems/531788: the river boat delta duchess paddled upstream at 12 km/h, stopped for 2 hours of sight seeing, and paddled back at 18 km/h. how far upstream did the boat travel if the total time for the trip, including the stop, was 7 hours?
1 solutions

Answer 350658 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 14:25:41 (Show Source):
You can put this solution on YOUR website!
the river boat delta duchess paddled upstream at 12 km/h, stopped for 2 hours of sight seeing, and paddled back at 18 km/h.
how far upstream did the boat travel if the total time for the trip, including the stop, was 7 hours
:
We only care about the traveling time which is 5 hrs
:
Let d = one way distance
:
Write a time equation: time = dist/speed
:
up time + down time = 5 hrs
d%2F12 + d%2F18 = 5
Multiply by 36 to get rid of the denominators, results:
3d + 2d = 36(5)
5d = 180
d = 180/5
d = 36 miles upstream
:
:
Check this by finding the actual time each way
36/12 = 3 hrs
36/18 = 2 hrs
-------------
totals: 5 hrs


Exponents/531816: How do I simplify, instructions are "use rational exponents to simplify"
this please:
^4 sqrt x^-28
I don't understand how a NEGATIVE power will affect the ^4 sqrt x
Please help.
Thank you!
~Adelaide
1 solutions

Answer 350657 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 14:16:55 (Show Source):
You can put this solution on YOUR website!
simplify"
this please:
^4 sqrt x^-28
Assume the problem is the 4th root of x^-28, written here like this:
4sqrt%28x%5E-28%29
remember you can always get rid of negative exponent using it's reciprocal
4sqrt%281%2Fx%5E28%29
In order to understand this we can write it

extract the 4th root of each and we have

which is
1%2Fx%5E7
:
But we can sum all this up in one sentence, the 4th root of the 28th power = 7


Rate-of-work-word-problems/531897: A 3-men crew can do a certain job in 4 hours, while it takes a 4-men crew to do the same job 3 hours. How long will it take to complete the job if two crews work together, and one worker from the second crew was 1 hour late? Thank you
1 solutions

Answer 350654 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 13:55:25 (Show Source):
You can put this solution on YOUR website!
A 3-men crew can do a certain job in 4 hours, while it takes a 4-men crew to do the same job 3 hours.
How long will it take to complete the job if two crews work together, and one worker from the second crew was 1 hour late?
:
We know that the job requires 12 man-hours to complete (3*4 or 4*3)
:
Let's try and determine how long it would take the 2nd crew to do the job if one guy was 1 hr late (h).
:
3 guys work the whole time, one guy works 1 hr less
3h + 1(h-1) = 12
3h + h - 1
4h = 12 + 1
4h = 13
h = 13/4
h = 3.25 hrs to do the job under these conditions
:
Now using a standard, shared work equation where the completed job = 1
Crew 1 + crew 2 = completed job
t%2F4 + t%2F3.25 = 1
multiply by 13 to clear the denominators
3.25t + 4t = 13
7.25t = 13
t = 13%2F7.25
t = 1.793 hrs which is 1 hr + .793(60) ~ 1 hr 48 min
:
Did this make sense? Let me know if you find out I am wrong on this one. C
:


Linear-equations/531851: I need help with eliminations ,
3x-y=5
x-2y=11
1 solutions

Answer 350634 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 09:22:02 (Show Source):
You can put this solution on YOUR website!
3x - y = 5
x - 2y = 11
Multiply the 1st equation by -2, add to the 2nd equation
-6x + 2y = -10
+ x - 2y = 11
----------------adding eliminates y, find x
-5x = 1
x = 1%2F%28-5%29
x = -.2
:
Use the 2nd equation to find y
-.2 - 2y = 11
-2y = 11 + .2
-2y = 11.2
y = 11.2%2F%28-2%29
y = -5.6
:
:
Check those solutions in the 1st equation
3x - y = 5
3(-.2) - (-5.6) = 5
-.6 + 5.6 = 5
:
Summarize: x =-.2; y = -5.6


Travel_Word_Problems/531852: a car driven on a rough road on 25 kilometers per hour and on a concrete road on 70 kilometers per hour.it takes the car 5.5 hours to drive on 225 kilometers.how long does it take the car to drive on a concrete road?
1 solutions

Answer 350633 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 08:54:16 (Show Source):
You can put this solution on YOUR website!
a car driven on a rough road on 25 kilometers per hour and on a concrete road on 70 kilometers per hour.it takes the car 5.5 hours to drive on 225 kilometers.
how long does it take the car to drive on a concrete road?
:
Let t = time on a concrete road
Given the total time as 5.5 hrs, therefore
(5.5-t) = time on the rough road
;
Write a distance equation, dist = speed * time
:
Rough rd dist + smooth rd dist = 225 km
25(5.5-t) + 70t = 225
137.5 - 25t + 70t = 225
-25t + 70t = 225 - 137.5
45t = 87.5
t = 87.5%2F45
t = 1.944 hrs or 1 + .944(60) = 1 hr 57 min on the smooth road
;
:
Check this by finding the dist at each speed, (5.5-1.944=3.556)
25*3.556 = 88.89 km
70*1.944 = 136.10 km
----------------
total km: 224.99 km


Permutations/531832: how many 5 digit even numbers are there?
1 solutions

Answer 350629 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 08:30:55 (Show Source):
You can put this solution on YOUR website!
how many 5 digit even numbers are there?
%28100000-9999%29%2F2 ~ 45000


Average/531824: If I miss 12 problems on a 41 problem test what is my score?
1 solutions

Answer 350628 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 08:21:03 (Show Source):
You can put this solution on YOUR website!
If I miss 12 problems on a 41 problem test what is my score
:
That means you got 41-12 = 29 problems right
29%2F41 * 100 = 70.7 %


Age_Word_Problems/531854: PLEASE I NEED IT ASAP! A man is 27 years older than his son and in 10 years, he will be twice as old as his son. How old is each now?
1 solutions

Answer 350627 by ankor@dixie-net.com(15653) About Me  on 2011-11-15 08:14:43 (Show Source):
You can put this solution on YOUR website!
A man is 27 years older than his son and in 10 years, he will be twice as old as his son. How old is each now?
:
Let m = man's present age
Let s = son's present age
:
Write an equation for each statement:
:
"A man is 27 years older than his son"
m = s + 27
:
"in 10 years, he will be twice as old as his son."
m + 10 = 2(s+10)
m + 10 = 2s + 20
m = 2s + 20 - 10
m = 2s + 10
:
From the 1st statement, replace m with (s+27)
s + 27 = 2s + 10
27 - 10 = 2s - s
17 = s
:
Son is 17 years old, I'll let you find the man's age, check your solutions in the 2nd statement
:
Hey! Try not to wait til the last minute! C





Rational-functions/531361: Please help me. I am confused. How do I solve these by factoring?
3x^2 -2x = 0
and
9x^2 -1 = 0
Thanks so much!
1 solutions

Answer 350584 by ankor@dixie-net.com(15653) About Me  on 2011-11-14 21:41:24 (Show Source):
You can put this solution on YOUR website!
Please help me. I am confused. How do I solve these by factoring?
3x^2 -2x = 0
Factor out x
x(3x - 2) = 0
Two solutions
x = 0
and
3x = 2
x = 2%2F3
:
and
9x^2 - 1 = 0
This is the difference of squares
(3x + 1)(3x -1) = 0
Two solutions
3x = -1
x = -1%2F3
and
x = 1%2F3


Polynomials-and-rational-expressions/531598: How do I factor:
7-6b-b^2=
? Thank you
1 solutions

Answer 350536 by ankor@dixie-net.com(15653) About Me  on 2011-11-14 19:29:04 (Show Source):
You can put this solution on YOUR website!
How do I factor:
7-6b-b^2=
We usually write it
-b^2 - 6b + 7 = 0
Easier to factor if b^2 is positive, multiply by -1 and you have
b^2 + 6b - 7 = 0
-7 only has two possible factors, we know one is neg and one positive
(b _ 1)(b _ 7) = 0
Choose the signs that will give you 6 as the coefficient of b
(b - 1)(b + 7) = 0
:
Check this by FOILing (b+7)(b-1) = b^2 - b + 7b - 7 = b^2 + 6b - 7
Multiply by -1 to get the original problem -b^2 - 6b + 7


Rate-of-work-word-problems/531209: A 5-horsepower (hp) pump can empty a pool in 5 hours. A smaller, 2-hp pump can empty a pool in 8 hours. The pumps are used together to begin emptying this pool. After two hours, the 2-hp pump breaks down. How long will it take the larger pump to finish emptying the pool?
1 solutions

Answer 350396 by ankor@dixie-net.com(15653) About Me  on 2011-11-14 11:05:49 (Show Source):
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A 5-horsepower (hp) pump can empty a pool in 5 hours.
A smaller, 2-hp pump can empty a pool in 8 hours.
The pumps are used together to begin emptying this pool.
After two hours, the 2-hp pump breaks down.
How long will it take the larger pump to finish emptying the pool?
:
Let t = additional time to finish emptying the pool
Let the completed job = 1, (an empty pool)
:
%28%28t%2B2%29%29%2F5 + 2%2F8 = 1
multiply by 40 to clear the denominators, results:
8(t+2) + 5(2) = 40
8t + 16 + 10 = 40
8t + 26 = 40
8t = 40 - 26
8t = 14
t = 14/8
t = 1.75 more hrs for the large pump to empty the pool
:
:
Check that (the large pump operates for a total of 3.75 hrs)
3.75%2F5 + 2%2F8 =
.75 + .25 = 1


Numbers_Word_Problems/531119: The units digit is 1 more than 3 times the tens digit in a two digit number. The number represented when the digits are interchanged is 8 times the sum of the digits. Find the original number.
1 solutions

Answer 350395 by ankor@dixie-net.com(15653) About Me  on 2011-11-14 10:54:10 (Show Source):
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The units digit is 1 more than 3 times the tens digit in a two digit number.
The number represented when the digits are interchanged is 8 times the sum of the digits.
Find the original number.
:
Let x = the 10's digit
Let y = the units
then
10x+y = the number
:
Write an equation for each statement:
:
"The units digit is 1 more than 3 times the tens digit"
y = 3x + 1
:
"The number represented when the digits are interchanged is 8 times the sum of the digits."
10y + x = 8(x+y)
:
You should be able to solve it now


Rate-of-work-word-problems/531211: An air rescue plane averages 300 miles per hour in still air. It carries fuel for 5 hours of flying time. If, upon takeoff, it encounters a head wind of 30 miles per hour, how far can it fly and return safely? (Assume that the wind remains constant)
1 solutions

Answer 350372 by ankor@dixie-net.com(15653) About Me  on 2011-11-14 08:50:21 (Show Source):
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An air rescue plane averages 300 miles per hour in still air.
It carries fuel for 5 hours of flying time.
If, upon takeoff, it encounters a head wind of 30 miles per hour, how far can it fly and return safely?
(Assume that the wind remains constant)
:
300 - 30 = 270 mph the ground speed against the wind
300 + 30 = 330 mph the ground speed with the wind
:
let d = the one way distance to point of no return
:
Write a time equation, time = dist/speed
:
Outbound time + return time = 5 hrs
d%2F270 + d%2F330 = 5
multiply by 2970 to get rid of the denominators, results
11d + 9d = 2970(5)
20d = 14850
d = 14850%2F20
d = 742.5 mi, but it says "safely", you would never cut it that close; I would say 650 max.
:
:
Confirm this by finding the actual time for each trip
742.5/270 = 2.75 hrs
742.5/330 = 2.25 hrs
---------------------
totals time: 5 hrs


Travel_Word_Problems/530762: A boat travels 15 miles upstream and returns. If the boat travels 14 mph in still water, find the speed of the currrent if the total trip takes 2 hours and 20 minutes.
I really only want to understand how to set the problem up, I have no problem with the algebra part :). Thank you so much to whoever helps me.
1 solutions

Answer 350307 by ankor@dixie-net.com(15653) About Me  on 2011-11-13 19:46:20 (Show Source):
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A boat travels 15 miles upstream and returns.
If the boat travels 14 mph in still water, find the speed of the current if the total trip takes 2 hours and 20 minutes.
:
Let c = the speed of the current
then
(14+c) = effective speed downstream
and
(14-c) = effective speed upstream
:
Change 2 hrs 20 min to 7%2F3 hrs
:
Write a time equation: time = dist/speed
:
Upstream time + downstream time = 2 hrs 20 min
15%2F%2814-c%29 = 15%2F%2814%2Bc%29 = 7%2F3


Travel_Word_Problems/530542: A truck is 300 miles due east of a car and is traveling at a constant speed of 30 miles per hour. Meanwhile, the car is going north at a constant speed of 60 miles per hour. Express the distance between the car and truck as a function of time
1 solutions

Answer 350149 by ankor@dixie-net.com(15653) About Me  on 2011-11-12 21:52:14 (Show Source):
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A truck is 300 miles due east of a car and is traveling at a constant speed of 30 miles per hour.
Meanwhile, the car is going north at a constant speed of 60 miles per hour.
Express the distance between the car and truck as a function of time
:
Assuming the truck is traveling east, let t = travel time of both
The distance between the two will be the hypotenuse of a right triangle
f(t) = sqrt%28%2860t%29%5E2%2B%28300%2B30t%29%5E2%29


Exponential-and-logarithmic-functions/530286: I need you help with this question:
The change in the population of a township founded in 1930 can be described by the function P(t)=10000+e%5E-0.02t+. At what rate is the population changing every year?
Ps: t is on the same line like 0.02, means 0.02 times t.
1 solutions

Answer 350129 by ankor@dixie-net.com(15653) About Me  on 2011-11-12 21:00:32 (Show Source):
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I need you help with this question:
The change in the population of a township founded in 1930 can be described by the function P(t)=10000*e^(-0.02t).
At what rate is the population changing every year?
:
The population would be losing 2% every year
:
Check on the graph, the given equation is red, -2% per year is green
:


Equations/530375: Three boxes of cookies are labelled A, B, and C. It is known that boxes A and B together contain 35 cookies, boxes A and C contain 28 cookies, and boxes B and C contain 37 cookies. How many cookies are in each box?
1 solutions

Answer 350027 by ankor@dixie-net.com(15653) About Me  on 2011-11-12 14:22:27 (Show Source):
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Three boxes of cookies are labeled A, B, and C.
It is known that boxes A and B together contain 35 cookies, boxes A and C contain 28 cookies, and boxes B and C contain 37 cookies.
How many cookies are in each box?
:
Add all three equations of each box
A + B + 0 = 35
A + 0 + C = 28
0 + B + C = 37
--------------
2A + 2B + 2C = 100
simplify divide by 2
A + B + C = 50
A + B + 0 = 35
----------------Subtract the 1st equation, eliminates A & B, find C
C = 15 in box C
:
A + C = 28
A + 15 = 28
A = 28 - 15
A = 13 in box A
:
B + C = 37
B + 15 = 37
B = 37 - 15
B = 22 in Box B
:
You can confirms these solutions in the given statements


Travel_Word_Problems/530220: How do you solve this problem: How far does the tip of the minute hand of a clock move in 175 minutes if the hand is 4.8 inches long?
1 solutions

Answer 349964 by ankor@dixie-net.com(15653) About Me  on 2011-11-11 21:31:45 (Show Source):
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How far does the tip of the minute hand of a clock move in 175 minutes if the hand is 4.8 inches long?
:
Find how many times the minutes hand makes it around the clock in 175 min
175%2F60 = 2.9167 times
:
Multiply this by the circumference of the clock assuming the radius is 4.8"
2.9167 * 2%2Api%2A4.8 = 87.96 inches in 175 min


Polynomials-and-rational-expressions/530191: Find the factor of:
2a+7 3a-4
--------- - ------------
a^2-2a-15 a^2-7a+10
1 solutions

Answer 349956 by ankor@dixie-net.com(15653) About Me  on 2011-11-11 21:20:04 (Show Source):
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Find the factor of:
%282a%2B7%29%2F%28a%5E2-2a-15%29 - %283a-4%29%2F%28a%5E2-7a%2B10%29
:
Factor
%282a%2B7%29%2F%28%28a-5%29%28a%2B3%29%29%29 - %283a-4%29%2F%28%28a-5%29%28a-2%29%29
:
The common denominator: (a-5)(a+3)(a-2)
;
%28%28a-2%29%282a%2B7%29+-+%28a%2B3%29%283a-4%29%29%2F%28%28a-5%29%28a%2B3%29%28a-2%29%29
:
FOIL; Remove brackets:
%28%282a%5E2%2B3a-14%29+-+%283a%5E2%2B5a-12%29%29%2F%28%28a-5%29%28a%2B3%29%28a-2%29%29 = %28%282a%5E2%2B3a-14+-+3a%5E2-5a%2B12%29%29%2F%28%28a-5%29%28a%2B3%29%28a-2%29%29
:
combine like terms and you have:
%28%28-a%5E2-2a-2%29%29%2F%28%28a-5%29%28a%2B3%29%28a-2%29%29
:
That's about all you can do with it


Linear-systems/530089: Use the method of substitution to solve the system:(Enter your answer(s) as ordered pair(s). If there is more than one ordered pair, use commas between ordered pairs.)
xy=2
5x-y+9=0
1 solutions

Answer 349950 by ankor@dixie-net.com(15653) About Me  on 2011-11-11 20:54:51 (Show Source):
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xy = 2
y = 2%2Fx
5x - y + 9 = 0
substitute 2/x for y
5x - 2%2Fx + 9 = 0
Mult equation by x
5x^2 - 2 + 9x = 0
a quadratic equation
5x^2 + 9x - 2 = 0
Factors to
(5x - 1)(x + 2) = 0
two solutions
5x = 1
x = .2
and
x = -2
:
Find y when x = .2
.2y = 2
y = 2/.2
y = 10
Ordered pair, .2, 10
:
Find y when x = -2
-2y = 2
y = 2/-2
y = -1
Ordered pair -2, -1


Equations/530179: Solve the problem by stating the equation you would use to solve and then solving it. Be sure to show all of your work.
In a local election, 25,800 people voted. This was an increase of 5% over the last election. How many people voted in the last election? Round to the nearest whole person.

1 solutions

Answer 349948 by ankor@dixie-net.com(15653) About Me  on 2011-11-11 20:51:19 (Show Source):
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1.05x = 25800


Travel_Word_Problems/530172: a train travels 180 miles in an hour less time than a bus traveling the same distance. if the speed of the bus is 15 mph slower that the speed of the train, find the speed of the train and bus?
1 solutions

Answer 349927 by ankor@dixie-net.com(15653) About Me  on 2011-11-11 19:24:21 (Show Source):
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a train travels 180 miles in an hour less time than a bus traveling the same distance.
if the speed of the bus is 15 mph slower that the speed of the train, find the speed of the train and bus?
:
Let s = speed of the bus
then
(s+15) = speed of the train
:
Write a time equation, time = dist/speed
:
Bus time - train time = 1 hr
180%2Fs - 180%2F%28s%2B15%29 = 1
;
multiply by s(s+15); results:
180(s+15) - 180s = s(s+15)
180s + 2700 - 180s = s^2 + 15s
:
a quadratic equation
s^2 + 15s - 2700 = 0
:
Factor to
(s+60)(s-45) = 0
:
the positive solution
s = 45 mph is the speed of the bus
then
45 + 15 = 60 mph is the speed of the train
:
:
Check this by finding the times of each
180/45 = 4 hrs
180/60 = 3 hrs
--------------
differ: 1 hrs


Geometry_Word_Problems/530133: "Water weighs 62.4 lbs per cubic foot. What is the weight of the water in a filled pool 63 feet long, 29 feet wide and 8 inches deep, to the nearest tenth of a pound?"
1 solutions

Answer 349921 by ankor@dixie-net.com(15653) About Me  on 2011-11-11 18:46:28 (Show Source):
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"Water weighs 62.4 lbs per cubic foot.
What is the weight of the water in a filled pool 63 feet long, 29 feet wide and 8 inches deep, to the nearest tenth of a pound?"
:
63*29*8%2F12*62.4 = 76,003.2 lbs


Polynomials-and-rational-expressions/530032: Help me to divide 3x^2-5x-2/6x^2-3x by -x^2-x+6/2x^2+5x-3
1 solutions

Answer 349901 by ankor@dixie-net.com(15653) About Me  on 2011-11-11 16:20:09 (Show Source):
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%283x%5E2-5x-2%29%2F%286x%5E2-3x%29
---------------
%28-x%5E2-x%2B6%29%2F%282x%5E2%2B5x-3%29
Invert the dividing fraction and multiply
%283x%5E2-5x-2%29%2F%286x%5E2-3x%29 * %282x%5E2%2B5x-3%29%2F%28-x%5E2-x%2B6%29
Factor out -1, changes the signs on the 2nd denominator
%283x%5E2-5x-2%29%2F%286x%5E2-3x%29 * %282x%5E2%2B5x-3%29%2F%28-1%28x%5E2%2Bx-6%29%29
Factor
%28%283x%2B1%29%28x-2%29%29%2F%283x%282x-1%29%29 * %28%282x-1%29%28x%2B3%29%29%2F%28-1%28x%2B3%29%28x-2%29%29
:
Cancel out x+3, x-2, 2x-1
%28%283x%2B1%29%29%2F%283x%29 * -1 = -%28%283x%2B1%29%29%2F%283x%29


Miscellaneous_Word_Problems/529994: What is the equation of the line with an x-intercept of -1 and a y-intercept of 2?
1 solutions

Answer 349889 by ankor@dixie-net.com(15653) About Me  on 2011-11-11 15:38:18 (Show Source):
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What is the equation of the line with an x-intercept of -1 and a y-intercept of 2?
we have
x = -1, y = 0, therefore one factor (x+1)
x = 0, y = 2, In the form ax^2 + bx + c, the 3rd term (c) = 2
:
therefore the other factor: (x+2), to get the 3rd term which is 2
FOIL (x+1)(x+2) = x^2 + 3x + 2 is the equation
:
Did this makes sense to you?