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Sequences-and-series/573364: What is the Nth equation of the following pattern?
Figure 1; 3 tiles
Figure 2; 5 tiles
figure 3; 7 tiles etc.
(and I know how the pattern grows, I just need to know what the equation is)
1 solutions
Answer 368756 by scott8148(6628)   on 2012-02-15 18:21:27 (Show Source):
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Human-and-algebraic-language/573352: Christy has a coin collection of nickels and dimes. She has 28 coins worth $2.25. How many of each coin does Christy have?
I know that .05n + .10D = $2.25
I also know that n+d=28
I can figure out these types of problems in my head, but I can't seem to do it using an algebraic equation.
1 solutions
Answer 368753 by scott8148(6628) on 2012-02-15 18:17:26 (Show Source):
You can put this solution on YOUR website!your equations can be used for substitution or elimination
n + d = 28 ___ n = 28 - d
5n + 10d = 225 ___ substituting ___ 5(28 - d) + 10d = 225
140 - 5d + 10d = 225 ___ 5d = 85
solve for d, then substitute back to find n
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Triangles/573316: The congruent sides of an isosceles triangle measure 6cm, and the base measures 8cm. What is the area? I don't understand how you would find the necessary height of the triangle, or how the base of an isosceles triangle can be longer than the two other congruent sides. Thank you:).
1 solutions
Answer 368728 by scott8148(6628) on 2012-02-15 17:10:31 (Show Source):
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Age_Word_Problems/573281: In 1993, the life expectancy of males in a certain country was 67.7 years. In 2000, it was 66.5 years. Let E represent the life expectancy in year t and let t represent the number of years since 1993.
I have tried for a whole day using formulas from others that were similiar and plugging the numbers in but I can not figure it out. Please help. It will be much appreciated
1 solutions
Answer 368725 by scott8148(6628) on 2012-02-15 16:59:56 (Show Source):
You can put this solution on YOUR website!from 1993 to 2000 the life expectancy decreased from 67.7 to 66.5
this change of -1.2yr per 7 yrs would be the slope of a linear graph
E = (-1.2/7)t + 67.7
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Miscellaneous_Word_Problems/573257: I need some help getting this problem set up.I know one has to travel back and forth so that limits to one at a time to cross at the slowest pace.Just getting confused.
Four people are trying to cross a bridge in the dark. The bridge is old, and can only hold two of the people at any one time. They have only one flashlight, which must be carried by someone each time the bridge is crossed. The flashlight is weak, so it is not possible to stand in the middle of the bridge and guide someone across. Each person must walk across the bridge and either carry the light or walk with someone who is carrying the light. The fastest person can cross the bridge in one minute, the second fastest needs two minutes, the third fastest crosses in five minutes, and the slowest takes ten minutes. What is the shortest amount of time that all four can cross the bridge.
1 solutions
Answer 368724 by scott8148(6628) on 2012-02-15 16:47:53 (Show Source):
You can put this solution on YOUR website!the two fastest cross and one brings back the light
the two slowest cross, and the fastest person (from the first crossing) brings back the light
the two fastest cross for the last time
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Functions/573197: Writing functions from roots:
Degree of 4 and roots are 2i, 3, and 6
and
Degree of 5 and roots are 0, 1, 2, plus or minus √31
Thanks in advance I really appreciate it ;)
1 solutions
Answer 368712 by scott8148(6628) on 2012-02-15 15:15:29 (Show Source):
You can put this solution on YOUR website!1st nugget ___ if r is a root of a function, then x-r is a factor
2nd nugget ___ complex roots (containing i) occur in conjugate pairs (a+bi and a-bi)
f(x) = (x - 2i)(x + 2i)(x - 3)(x - 6)
g(x) = (x)(x - 1)(x - 2)(x - √31)(x + √31)
you can multiply the factors together to get the expanded form of the function
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Square-cubic-other-roots/573141: What is the square root of 1700? This is what I have so far:
1700 412
-16
--
81 100
81
----
82 1900
Now we are lost. I am a homeschool mom trying to help my son understand this.
I have the answer, but not how to get the answer, so if you could include the math for each step I would appreciate it. Thank you for your help
1 solutions
Answer 368694 by scott8148(6628) on 2012-02-15 13:10:57 (Show Source):
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Quadratic-relations-and-conic-sections/572850: how do i complete the square with a ellipse equation? the equation im having issues with is 49x^2+36y^2+686x-360y+1537=0. please help.
1 solutions
Answer 368559 by scott8148(6628) on 2012-02-14 21:22:11 (Show Source):
You can put this solution on YOUR website!49(x^2 + 14x) + 36(y^2 - 10y) = -1537
49(x^2 + 14x + 49) + 36(y^2 - 10y + 25) = -1537 + (49 * 49) + (36 * 25)
49(x + 7)^2 + 36(y - 5)^2 = -1537 + (49 * 49) + (36 * 25)
[49(x + 7)^2 + 36(y - 5)^2] / (49 * 36) = [-1537 + (49 * 49) + (36 * 25)] / (49 * 36)
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Age_Word_Problems/572727: Marco and his dad have an age difference of 25. The sum of their ages is 43. How old is Marco. I subtracted 25 from 43, but the choices are 7,9,12,32. I come up with 18
1 solutions
Answer 368493 by scott8148(6628) on 2012-02-14 16:51:10 (Show Source):
You can put this solution on YOUR website!Marco's dad is 25 years older than Marco, his age is Marco's age PLUS 25
so the sum of their ages is ___ Marco plus Marco plus 25
the solution you found is twice Marco's age
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�t�e�s�t/572635: How many minutes will it take to completely fill a water tank with a capacity of 3750 litres if the water is
being pumped into the tank at the rate of 800 litres per minute and is being drained out of the tank at
the rate of 300 litres per minute?
i jus started with net part filled =1/800 - 1/300
for 1 min = 500/2400 filled ....after this i have no idea to proceed ....
1 solutions
Answer 368468 by scott8148(6628) on 2012-02-14 12:11:11 (Show Source):
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Length-and-distance/572638: In the same amount of time a new production assembly robot can assemble 8 times as many
transmissions as an old assembly line. If the new robot can assemble 'x' transmissions per hour, how
many transmissions can the new robot and the old assembly line produce together in five days of round
the clock production.
for this i started with both robots 1 hr work = x+ x/8 = 9x / 8 ....after this i have no idea ...can anyone help me....?
1 solutions
Answer 368467 by scott8148(6628) on 2012-02-14 12:07:45 (Show Source):
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Coordinate-system/572582: Find an equation of the circle that satisfies the given conditions. (Give your answer in terms of x and y.)
Center
(4, −5)
and passes through
(9, 4)
1 solutions
Answer 368466 by scott8148(6628) on 2012-02-14 12:03:12 (Show Source):
You can put this solution on YOUR website!the general equation for a circle is ___ (x - h)^2 + (y - k)^2 = r^2 ___ this is a circle centered at (h,k) with a radius of r
in this case, r is the distance between (4,-5) and (9,4)
___ by Pythagoras (the distance formula) ___ r^2 = (4 - 9)^2 + (-5 - 4)^2
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Linear-systems/572618: so im having problems in my algebra class, how would i do an equation like this ->
Choose the correct first step(s) to solve the system using elimination.
4x + 7y = 6 and 6x + y = 2
(example problem)
1)7(6x + y = 2) → -42x - 7y = -14
2)4x + 7y = 6x + y
3)y = -6x + 20 → 4x + 7(-6x + 20) = 6
4)(4x + 7y) + (6x + y) = 8
5)(4x + 7y) - (6x + y) = 4
1 solutions
Answer 368462 by scott8148(6628) on 2012-02-14 11:48:14 (Show Source):
You can put this solution on YOUR website!with elimination, you try to get the coefficients of one of the variables to be equal but opposite in the two equations
___ that way, when you add the two equations; the variable will be eliminated
the 1st option multiplies the 2nd equation by -7 to get equal but opposite coefficients for the y-terms
when you add the two equations ___ 4x + 7y - 42x - 7y = 6 - 14
the y-terms are eliminated ___ -38x = -8
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Percentage-and-ratio-word-problems/572340: a dealer sold 200 tennis racquets. Some were sold at $18 each and the rest were sold at $33 each. The total reciepts from these sales were $4800. How many $18 racquets did he sell?
I can get the average of $24, but am drawing a blank on the actual formula to use.
1 solutions
Answer 368384 by scott8148(6628) on 2012-02-13 20:11:31 (Show Source):
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Number-Line/572305: The number line I am trying to solve is __, __, __, 18, __, __, __, __, __, 48
1 solutions
Answer 368362 by scott8148(6628) on 2012-02-13 18:56:48 (Show Source):
You can put this solution on YOUR website!48 is the 6th number after 18 , so the common difference (d) has been added 6 times
18 + 6d = 48 ___ 6d = 30 ___ d = 5
so the difference between adjacent numbers is 5
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Rectangles/572259: A rectangles's length is 8 meters more than three times the width. The perimeter is 80 meters. What is the lenght?
8m
24m
32m
40m
I believe the answer is 24 or 32 but its tricky to me because of the 8 meters more part of the question. Also What is the difference between width and length. I thought they were the same. I understand that 2(w + h) = Perimeter
Thats why I think it is 32 or 24
Im sway to 24 when the 8 more is applied because it would mean that the height would have to be more than 8. HELP
1 solutions
Answer 368360 by scott8148(6628) on 2012-02-13 18:47:11 (Show Source):
You can put this solution on YOUR website!"A rectangles's length is 8 meters more than three times the width" ___ L = 3W + 8
"The perimeter is 80 meters" ___ 2L + 2W = 80 ___ L + W = 40 ___ W = 40 - L
substituting ___ L = 3(40 - L) + 8 ___ L = 120 - 3L + 8 ___ 4L = 128
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Miscellaneous_Word_Problems/572262: Kristin spent $131 on shirts. Fancy shirts cost $28 and plain shirts cost $15. If she bought a total of 7 then how many of each kind did she buy?
How would you go about solving this problem? My step-daughter has it on her homework and she is having me check her work and it has been 20 years since I took algebra and I am at a lose as to where to even begin this problem.
1 solutions
Answer 368358 by scott8148(6628) on 2012-02-13 18:40:10 (Show Source):
You can put this solution on YOUR website!"Kristin spent $131 on shirts. Fancy shirts cost $28 and plain shirts cost $15" ___ 28f + 15p = 131
"she bought a total of 7" ___ f + p = 7 ___ p = 7 - f
substituting the equivalent value of p ___ 28f + 15(7 - f) = 131
28f + 105 - 15f = 131 ___ 13f = 26
solve for f , then substitute back to find p
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Equations/572284: trying to help son with math homework, please help.
45 divided by 9=___ divided by 8
12 divided by ____=15 divided by 5
1 solutions
Answer 368354 by scott8148(6628) on 2012-02-13 18:30:00 (Show Source):
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decimal-numbers/572273: How would you write 10 to the -6 in decimal form? Also, another problem, 6x10 to the -3? If you can send me the answer, and how you got that, as SOON as possible, like later on today, or early-bout 7 or 8 in the morning, I would TRULY AND GLADLY appreciate it!
2/13/12
1 solutions
Answer 368351 by scott8148(6628) on 2012-02-13 18:21:18 (Show Source):
You can put this solution on YOUR website!10^2 = 100
10^1 = 10
10^0 = 1
10^-1 =.1
10^-2 = .01
follow the pattern to 10^-6
6x10^-3 is just what it says , 6 multiplied by 10^-3
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Geometry_Word_Problems/572195: You and seven of your friends (8 people total)order a pizza frOm Dominios for $2.00 per person. It has a 18 inch diameter. You split the pizza evenly between all of you
You and three of your friends (4people total) each order 3 slices of pizza from Pizza Hut for $5 total per person. Each slice is 1/8 of a pizza with a 19 inch diameter
Which deal is better?
Your help will be greatly appreciated.
On my own I discovered that:
Dominos pizza will feed eight people for the cost of $16.00 and I estimated that each slice will be 2.25inches
Pizza huts pizza will feed. Four people for the cost of $15.00 and will provide 12 slices at 2.375 inches per slice
1 solutions
Answer 368336 by scott8148(6628) on 2012-02-13 16:08:59 (Show Source):
You can put this solution on YOUR website!the area of a circle (pizza) is, pi (not pie) times the radius squared
the best deal is most area per dollar
D ___ (pi * 9^2) / 16
P ___ (pi * 9.5^2)(3/8) / 5
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Functions/572132: Let f(x) = 6x − 8 and g(x) = 3x + 9.Write a formula for the following function.
g − f
I tried 3x+9-6x-8 and it was wrong, I also tried the simplified version, -3x+1 and it was wrong as well.
1 solutions
Answer 368306 by scott8148(6628) on 2012-02-13 14:22:19 (Show Source):
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Word_Problems_With_Coins/572082: Ben has $2.25 in nickels and dimes. He has 6 more nickels than dimes. How many nickels does he have?
I've tried everything I know, but I cant seem to solve it :(
1 solutions
Answer 368282 by scott8148(6628) on 2012-02-13 12:53:45 (Show Source):
You can put this solution on YOUR website!"Ben has $2.25 in nickels and dimes" ___ 5n + 10d = 225
"He has 6 more nickels than dimes" ___ n = d + 6
substituting ___ 5(d + 6) + 10d = 225 ___ 5d + 30 + 10d = 225 ___ 15d = 195
solve for d, then substitute back to find n
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Word_Problems_With_Coins/571632: I have 15 coins;only pennies and dimes. The value of the coins is 80 cents. How many pennies and dimes do I have? Find your answer by creating a graph by using the X and Y-intercepts of the two equations.
I am in Algebra I. I have graphed these two equations on a 12x9 grid multiple times with no conclusion.X=Pennies and Y=Dimes. X+Y=15 and 0.01X+0.1Y=0.80
I cannon get a definate solution to the problem. Please help
1 solutions
Answer 368153 by scott8148(6628) on 2012-02-12 14:43:35 (Show Source):
You can put this solution on YOUR website!solving the equations algebraically ___ p + d = 15 and p + 10d = 80
subtracting the equations ___ p + 10d - (p + d) = 80 - 15 ___ 9d = 65 ___ d = 7 2/9
___ this would make p equal to ___ 15 - 7 2/9 or 7 7/9
since these "fractional" coins do not exist ; there seems to be an inconsistency in the problem
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Travel_Word_Problems/571298: A train leaves the terminal averaging 45 MPH. A second train leaves the same terminal 2 hours later, averaging 60 MPH. How long will it take the second train to catch up to the first train?
1 solutions
Answer 368043 by scott8148(6628) on 2012-02-11 14:42:09 (Show Source):
You can put this solution on YOUR website!the 1st train has a 90 mi (45 * 2) head start
the second train closes the distance at 15 mph (60 - 45)
how long to go 90 mi at 15 mph?
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Mixture_Word_Problems/571243: By weight one alloy has 40% Aluminum, 38% Copper and the rest Cadmium. The second alloy has 52%, 20% and 28% Aluminum, Copper, and Cadmium respectively. The Aluminum, Copper, and Cadmium content of the third alloy is 61%, 12% and 27% respectively. How much of each alloy must be mixed to produce 1000 Lbs of alloy with the following content of 50.2% Aluminum, 23.8% Copper and 26% Cadmium? I am completely stumped on how to figure this one out. Can someone help Please?
1 solutions
Answer 368040 by scott8148(6628) on 2012-02-11 14:37:59 (Show Source):
You can put this solution on YOUR website!let x = amount of 1st alloy , y = amount of 2nd alloy , and z = amount of 3rd alloy
you are given the amounts of the components in the final alloy
___ Al = (50.2%)(1000) = 502 lb
___ Cu = (23.8%)(1000) = 238 lb
___ Cd = (26%)(1000) = 260 lb
.4x + .52y + .61z = 502
.38x + .2y + .12z = 238
.22x + .28y + .27z = 260
solve the system of equations to find the amounts of the three alloys
you might want to think about Cramer's Rule
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