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rfer answered: 12726 problems
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percentage/486156: a coat was $270 with 40% off what was the original price?
1 solutions

Answer 332365 by rfer(12730) on 2011-08-25 19:03:23 (Show Source):

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270/0.60=$450

Numeric_Fractions/486153: The question I was asked was -2+-1+3/4 and my answer was -9/4. Is this right?
1 solutions

Answer 332364 by rfer(12730) on 2011-08-25 19:02:04 (Show Source):

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-8/4-4/4+3/4=-9/4
If your teachers wants a reduced fraction then =-2 1/4

Miscellaneous_Word_Problems/485958: If it takes 5 workers 12 hrs to unload a truck, how long will it take 6 workers?
1 solutions

Answer 332289 by rfer(12730) on 2011-08-25 09:39:22 (Show Source):

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5*12=6x
60=6x
x=10 hrs

Graphs/485964: Use the vertex formula to find the vertex of the quadratic function
f(x)=-x^2+6x-11
The vertex is ?
1 solutions

Answer 332288 by rfer(12730) on 2011-08-25 09:37:34 (Show Source):

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vertex=(3,-2)

Travel_Word_Problems/485967: what is the speed of a truck that travels 10. km in 10. minutes
1 solutions

Answer 332286 by rfer(12730) on 2011-08-25 09:32:27 (Show Source):

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60 kph

Equations/485841: what is the first step for 3k-5=7k-21?
please!!!!!!
explain the steps and clearly explain why do you have to do those steps: not, to get the ansmers. please explain, i am in 7th grade doing algerbra 1.
I have trouble doing multi-step equation. If that is one of the eastiest things in algerba 1 should i go to pre-algerbra? Its hard to do multi-step equations with both variables in both sides.
1 solutions

Answer 332205 by rfer(12730) on 2011-08-24 22:50:25 (Show Source):

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4k=16
k=4

Numbers_Word_Problems/485800: Two consecutive even integers have a sum of 26. What are the two integers?
1 solutions

Answer 332195 by rfer(12730) on 2011-08-24 21:50:21 (Show Source):

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x+x+2=26
2x=24
x=12
x+2=14

Linear-systems/485795: Determine if (1/2,-4) is a solution to 4x-3y=-10.
1 solutions

Answer 332194 by rfer(12730) on 2011-08-24 21:49:21 (Show Source):

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4x-3*-4=-10
4x+12=-10
4x=-10-12
4x=-22
x=-5.5
not a solution

Proportions/485824: 4/7x = 4/5
1 solutions

Answer 332193 by rfer(12730) on 2011-08-24 21:44:56 (Show Source):

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x=(4/5)/(4/7)
x=4/5*7/4
x=28/20
x=1 2/5

Linear-equations/485751: write an equation and draw a graph for the line with slope 3/2 that pass through point (-2,0)
1 solutions

Answer 332192 by rfer(12730) on 2011-08-24 21:43:13 (Show Source):

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0=3/2*-2+b
0=-3+b
b=3
---------------
y=3/2x+3

Numbers_Word_Problems/485756: The sum of two consecutive whole nombers is 57. What are the two numbers?
1 solutions

Answer 332191 by rfer(12730) on 2011-08-24 21:41:18 (Show Source):

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x+x+1=57
2x=56
x=28
x+1=29

Graphs/485786: I need to solve the linear equation 8=-3x-7
1 solutions

Answer 332190 by rfer(12730) on 2011-08-24 21:38:56 (Show Source):

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15=-3x
-5=x

Proportions/485807: when the cost of the car is multiplied by 0.05 the result $1760. find the cost of the car
1 solutions

Answer 332189 by rfer(12730) on 2011-08-24 21:37:52 (Show Source):

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1760/0.05=$35,200

expressions/485806: what number decreased by 77 equals -18?
1 solutions

Answer 332187 by rfer(12730) on 2011-08-24 21:36:22 (Show Source):

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77-18=59

Inverses/485178: 3r +1.5=r+4.5
1 solutions

Answer 331868 by rfer(12730) on 2011-08-23 21:54:58 (Show Source):

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2r=3
r=3/2

Linear-equations/485208: if the line passes through points (0,5) and (-2,9), the equation for the line is?
1 solutions

Answer 331865 by rfer(12730) on 2011-08-23 21:52:54 (Show Source):

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m=(9-5)/(-2-0)
m=4/-2
m=-2
-------------
y=mx+b
9=-2*-2+b
9=4+b
b=9/4
b=2.25
---------------
y=-2x+2.25

Numeric_Fractions/485183: what is 3/5x=15
1 solutions

Answer 331854 by rfer(12730) on 2011-08-23 20:59:30 (Show Source):

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x=15/(3/5)
x=15*5/3
x=75/3
x=25

Linear-equations/485084: What is an example of a nonlinear function?
1 solutions

Answer 331826 by rfer(12730) on 2011-08-23 18:15:48 (Show Source):

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something with an exponent

Linear-equations/485015: How do I find the slope of y= -2x +5. How do I find the value of x at which the 2 lines y=2x+1 and y= -1/4x + 3 intersect. I am completely confused, please if someone can show me step by step to get a solution to both of these. Thank you.
1 solutions

Answer 331825 by rfer(12730) on 2011-08-23 18:15:02 (Show Source):

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slope =m
y=mx+b
slope m=-2
-------------
y=2x+1
y=-1/4x+3
------------
2x+1=-1/4x+3
2x+1/4x=2
2 1/4x=2
x=2/(2 1/4)
x=2*4/9
x=8/9
------------
y=2(8/9)+1
y=16/9+1
y=25/9
y=2 7/9
------------
(8/9,0)
(0,2 7/9)
--------------

Numeric_Fractions/485016: 4/7+3/14=
1 solutions

Answer 331823 by rfer(12730) on 2011-08-23 18:06:47 (Show Source):

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8/14+3/14=11/14

Numeric_Fractions/485022: Finding Variables and Expressions:
What is number of inches in any number of feet?
1 solutions

Answer 331821 by rfer(12730) on 2011-08-23 18:05:04 (Show Source):

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=12x

Distributive-associative-commutative-properties/485019: how do you simplify 6+12-(4+n)
1 solutions

Answer 331816 by rfer(12730) on 2011-08-23 17:57:31 (Show Source):

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6+12-4-n
=14-n

Linear-equations/485034: i dont know how to solve linear equation problems!!! please help. i just started highschool and i am in accelerated geometry. i forgot everything!
1 solutions

Answer 331814 by rfer(12730) on 2011-08-23 17:55:50 (Show Source):

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post a problem

Rational-functions/485059: what is the slope and the y-intercept of the equation 4y=2x-10 ?
1 solutions

Answer 331812 by rfer(12730) on 2011-08-23 17:53:33 (Show Source):

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4y=2x-10
change to y-mx+b form
y=2/4x-10/4
y=1/2x-2 1/2
slope m=1/2
y int =-2 1/2

Inequalities/484554: what is the answers to:
13-4y=25
3/4x-5>7
-1/2x-7=23
1 solutions

Answer 331555 by rfer(12730) on 2011-08-22 18:36:32 (Show Source):

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13-4y=25
-4y=12
y=-3
------------
3/4x-5 > 7
3/4x > 7+5
3/4x > 13
x > 13*4/3
x > 52/3
x > 17 1/3
---------------
-1/2x-7=23
-1/2x=30
x=30*-2/1
x=-60

Linear-equations/484562: 7y+44=12y+11
1 solutions

Answer 331550 by rfer(12730) on 2011-08-22 18:32:03 (Show Source):

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-5y=-33
y=6.6

Expressions-with-variables/484469: -5(x+7)-5(1+x)-2x
1 solutions

Answer 331548 by rfer(12730) on 2011-08-22 18:30:49 (Show Source):

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-5x-35-5-5x-2x
=-12x-40

Equations/484536: 12(2j-6)
1 solutions

Answer 331546 by rfer(12730) on 2011-08-22 18:27:53 (Show Source):

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=24j-72

Equations/484555: I need help on algebra
1 solutions

Answer 331544 by rfer(12730) on 2011-08-22 18:27:06 (Show Source):

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post a problem.