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fractalier answered: 2101 problems
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I need with this problem please 1 1/3x-3 1/2=41/18 1 solutions
Answer 24372 by fractalier(2101) on 2006-05-22 12:16:52 (Show Source):
You can put this solution on YOUR website!Okay from
1 1/3x-3 1/2=41/18, let us rewrite it in improper fractions
(4/3)x - 7/2 = 41/18
If I multiply everything by the lowest common denominator, 18, I can cleasr all fractions...thus
18[(4/3)x - 7/2 = 41/18]
24x - 63 = 41
now add 63 and divide by 24
24x = 104
x = 104/24 = 13/3
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Expressions-with-variables/38859: using elimination to solve this system of equations, how would i solve
8x-3y=-11
2x-5y=27 1 solutions
Answer 24371 by fractalier(2101) on 2006-05-22 12:13:28 (Show Source):
You can put this solution on YOUR website!From
8x - 3y = -11
2x - 5y = 27
let us multiply the second equation by 4 and subtract it from the first, thus eliminating the x's...
8x - 3y = -11
-(8x - 20y = 108)
and we get
17y = -119
y = -7
and then by substituting we get
2x - 5(-7) = 27
2x + 35 = 27
2x = -8
x = -4
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Linear-equations/38873: PLease help me write the equation of the line with x-intercept (3, 0) and y-intercept (0, 2).
Thank You 1 solutions
Answer 24370 by fractalier(2101) on 2006-05-22 12:01:47 (Show Source):
You can put this solution on YOUR website!There is a special form of a line not taught very often called the intercept form and it goes like this
x/a + y/b = 1
where a and b are the x- and y-intercepts...
Here we have such a case and so
x/3 + y/2 = 1
now multiply by 6 and get
2x + 3y = 6
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Geometry_Word_Problems/38897: The height of a triangle is twice the base. The area is 9 square inches. find the area. 1 solutions
Answer 24368 by fractalier(2101) on 2006-05-22 11:32:32 (Show Source):
You can put this solution on YOUR website!The area is given as 9 -- is that what they really want? I doubt it...
The facts they give us are
h = 2b
and
A = 9
but we know that
A = (1/2)bh
so now substitute in everything and get
9 = (1/2)b(2b)
b^2 = 9
b = 3
Then h = 6.
This is probably what they wanted.
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Radicals/38912: (3radical a - 2 radical b) (3radical + 2radical b) 1 solutions
Answer 24365 by fractalier(2101) on 2006-05-22 11:23:22 (Show Source):
You can put this solution on YOUR website!If you mean
(3rad(a) - 2rad(b)) * (3rad(a) + 2rad(b))
then you have a sum times a difference which equals the difference of their squares, so you get
[3rad(a)]^2 - [2rad(b)]^2 =
9a - 4b
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Equations/38906: solve for t
P = 2pt/t+4
(P equals 2pt over t+4) solve for t 1 solutions
Answer 24364 by fractalier(2101) on 2006-05-22 11:20:27 (Show Source):
You can put this solution on YOUR website!From
P = (2pt) / (t + 4)
and assuming that P and p are different variables, multiply both sides by t + 4
P(t + 4) = 2pt
Pt + 4P = 2pt
now collect terms with t in them
Pt - 2pt = -4P
t(P - 2p) = -4P
t = -4p / (P - 2p)
If P and p are meant to be the same, then
t = 4
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Divisibility_and_Prime_Numbers/38857: Can someone help me solve this problem?
Julio works as a quality control expert in a beverage factory. The assembly line that he monitors produces about 20,000 bottles in a 24-hour period. Julio samples about 120 bottles an hour and rejects the line if he finds more than 1/50 of the sample to be defective. About how many defective bottles should Julio allow before rejecting the entire line?
Thanks!
Sher 1 solutions
Answer 24332 by fractalier(2101) on 2006-05-21 20:49:42 (Show Source):
You can put this solution on YOUR website!Well 1/50 of 120 bottles is 2.4 bottles...therefore he can allow two defective ones per hour before rejecting the whole line...the 3rd bad one and it's over...
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expressions/38856: evaluate the following expression
ab to the negative 1st power over c 1 solutions
Answer 24330 by fractalier(2101) on 2006-05-21 20:46:24 (Show Source):
You can put this solution on YOUR website!Okay from
a(b^-1) / c
we know that negative exponents on the top become positive exponents on the bottom, so this becomes
a / bc.
If the original problem was (ab)^-1 / c (it is not clear), then your answer is
1/abc
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Triangles/38788: The hypotenuse of a right triangle is 4 cm. longer than the one leg and 18 cm. longer than the other leg. Find the length of each side of the triangle. 1 solutions
Answer 24328 by fractalier(2101) on 2006-05-21 20:43:45 (Show Source):
You can put this solution on YOUR website!Call the shortest leg x.
The hypotenuse is x + 18.
The other leg is x + 14 since it is only 4 less than the hypotenuse.
Now apply the Pythagorean Theorem: a^2 + b^2 = c^2 and we get
x^2 + (x + 14)^2 = (x + 18)^2
x^2 + x^2 + 28x + 196 = x^2 + 36x + 324
now collecting and solving we get
x^2 - 8x - 128 = 0
(x - 16)(x + 8) = 0
x = 16 or x = -8
but distance is never negative so the short leg is 16 and the longer leg is 30. The hypotenuse is 34.
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Polynomials-and-rational-expressions/38853: This question is from textbook Beginning Algebra
Okay, I added, but am having trouble simplifiying...
could you please help me?
This is what I have so far...
x² 3x - 70
———————— + —————————
x + 10 x + 10
I got
x² + 3x - 70
——————————————
x + 10
how do I simplify that?
Thank you in advance for your help. 1 solutions
Answer 24325 by fractalier(2101) on 2006-05-21 20:34:25 (Show Source):
You can put this solution on YOUR website!Okay from
x^2 / x+10 + 3x-70 / x+10
we can add the numerator as they are since the denominators are the same, or what are called "like" denominators, so we simply get
(x^2 + 3x - 70) / (x + 10)
Now we factor the numerator and get
(x + 10)(x - 7) / (x + 10)
oh, what a surprise, the x + 10's cancel, leaving
the answer: x - 7
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Polynomials-and-rational-expressions/38855: This question is from textbook Beginning Algebra
Okay, I don't even know where to begin with this one...
Subtract
5/y-7 minus 1/y+1
Please help me !! LOL 1 solutions
Answer 24323 by fractalier(2101) on 2006-05-21 20:31:25 (Show Source):
You can put this solution on YOUR website!I teach my students a method called the "criss-cross" method...
Whenever you have fractions like this you can apply a short-cut...
Goes like this...
A/B + C/D = (AD + BC) / BD
no matter what A, B, C, and D are and it works for adding or subtracting...
so from
5/(y-7) - 1/(y+1)
we criss cross and get
[5(y + 1) - (y - 7)] / [(y - 7)(y + 1)] =
5y + 5 - y + 7 / [(y - 7)(y + 1)] =
4y + 12 / [(y - 7)(y + 1)]
and we're done...
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Miscellaneous_Word_Problems/38574: It takes Tom 4 hours to build a fence. If he hires Jack to help him, together they can do the job in just 3 hours. If jack built the same fence by himself, how long would it take him??
Thanks for answering!:-) 1 solutions
Answer 24112 by fractalier(2101) on 2006-05-19 17:10:33 (Show Source):
You can put this solution on YOUR website!We use the work problem formula
t/A + t/B = 1
t = time worked together
A = first guy's time alone
B = second guy's time alone
1 = one job or task
so plug in and get
3/4 + 3/B = 1
multiply all by 4B and get
3B + 12 = 4B
and
B = 12 hours
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Miscellaneous_Word_Problems/38577: A vending machine has $41.25 in it. There are 255 coins total and the machine only accepts nickels, dimes and quarters. There are twice as many dimes and nickels. How many of each coin are in the machine? 1 solutions
Answer 24110 by fractalier(2101) on 2006-05-19 17:07:57 (Show Source):
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Polynomials-and-rational-expressions/38591: I previously asked this and no one answered. Please help!!
Add. Express answer in simplest form
4x/x^2-18x+72 + 4/x-6 1 solutions
Answer 24107 by fractalier(2101) on 2006-05-19 17:04:45 (Show Source):
You can put this solution on YOUR website!From
4x/)x^2-18x+72) + 4/(x-6)
we factor the denominator of the first fraction and get
4x/(x-12)(x-6) + 4/(x-6)
Notice that if we multiply the second fractaion by (x-12)/(x-12), we will have common denominators...so
4x/(x-12)(x-6) + 4(x-12)/(x-6)(x-12) =
(4x + 4x - 48) / (x-6)(x-12) =
8x-48 / (x-6)(x-12) =
8(x-6) / (x-6)(x-12) =
8 / (x-12)
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Miscellaneous_Word_Problems/38578: Terry has 7 more quarters than dimes and has a total of $6.80. The number of quarters and dimes is 38. How many quarters and dimes does terry have?
Thanks for answering!:-) 1 solutions
Answer 24091 by fractalier(2101) on 2006-05-19 15:28:30 (Show Source):
You can put this solution on YOUR website!Let q = # of quarters. Thus their value is 25q.
Let d = # of dimes. Thus their value is 10d.
From the facts in the problem, we have
q + d = 38
25q + 10d = 680 ($6.80 expressed in cents)
We also have a third equation, not common in these problems (q = d + 7) which incidentally is impossible...
Let us solve the first for d and substitute into the second equation...
d = 38 - q
25q + 10(38 - q) = 680
25q + 380 - 10q = 680
15q = 300
q = 20 and then
d = 18
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Miscellaneous_Word_Problems/38575: The mat around a picture measures x inches across. The length of the picture with the mat is 40 inches, and the width of the picture with its mat is 24 inches. If the area of the picture is 192 square inches, find the dimensions of the picture.
Thanks for answering!:-) 1 solutions
Answer 24089 by fractalier(2101) on 2006-05-19 15:22:30 (Show Source):
You can put this solution on YOUR website!Since the border all along the picture is x, the length of just the picture is
40 - 2x (since x on top and bottom).
The width is then 24 - 2x, by the same logic.
And of course, A = LW = 192.
So, by substituting, we get
192 = (40 - 2x)(24 - 2x)
192 = 960 - 128x + 4x^2 or
4x^2 - 128x + 768 = 0
x^2 - 32x + 192 = 0
(x - 24)(x - 8) = 0
x = 24 or x = 8
but the border cannot be 24, that's too big.
So the border is 8 inches, and the dimensions of just the picture are
40 - 16 = 24 inches
by
24 - 16 = 8 inches
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Radicals/38572: 36. Show a complete solution.
Two positive numbers differ by 11, and their square roots differ by 1. Find the numbers.
1 solutions
Answer 24086 by fractalier(2101) on 2006-05-19 15:05:26 (Show Source):
You can put this solution on YOUR website!Let the numbers be x and y.
Then from the facts, we have
x - y = 11
sqrt(x) - sqrt(y) = 1
Let us solve the first one for x:
x = y + 11
Let us substitute that into the second equation.
sqrt(y + 11) - sqrt(y) = 1
We can rearrange this and then square both sides.
sqrt(y + 11) = sqrt(y) + 1
y + 11 = y + 2*sqrt(y) + 1
10 = 2*sqrt(y)
sqrt(y) = 5
y = 25
Thus x equals 36.
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Quadratic_Equations/38560: I need your help to solve this problem and also what are the steps to solve this problem.
The length of a hypotenuse of a right triangle is 2 feet more than the longer leg. The length of the longer leg is 7 feet more than the lenth of the shorter leg. Find the number of feet in length of each side of the right triangle.
1 solutions
Answer 24084 by fractalier(2101) on 2006-05-19 14:55:10 (Show Source):
You can put this solution on YOUR website!For every right triangle, a^2 + b^2 = c^2...
Let x = the length of the shorter leg.
Thus x + 7 is the longer leg and
x + 9 is the length of the hypotenuse...
So substituting into the Pythagorean Theorem, we have
x^2 + (x + 7)^2 = (x + 9)^2
x^2 + (x^2 + 14x + 49) = x^2 + 18x + 81
now collect like terms and solve for x
2x^2 + 14x + 49 = x^2 + 18x + 81
x^2 - 4x - 32 = 0
(x - 8)(x + 4) = 0
x = 8 and x = -4
but distances cannot be negative, so
x = 8
The other sides must be 15 and 17.
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