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Linear-equations/353909: im really good with numbers and algebra... but i suck at graphing equations and linear equations.
can any one please help me with the graphing
thanks.
1 solutions

Answer 252989 by rfer(12645) on 2010-10-09 14:29:05 (Show Source):

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post the question

Miscellaneous_Word_Problems/353922: Hi everyone! Really need some help on a math problem...
.
http://oi51.tinypic.com/e5g3cw.jpg
.
Thanks!
-Ghauri
1 solutions

Answer 252986 by rfer(12645) on 2010-10-09 14:27:11 (Show Source):

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post it

Angles/353921: The ratio of the complement of an angle to the supplement of the angle is 7:22. Find the measure of th angle, the complement, and the supplement.
1 solutions

Answer 252984 by rfer(12645) on 2010-10-09 14:23:28 (Show Source):

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90-7x=180-22x
15x=90
x=6
90-7x=48 compliment=42
180-22x=48 supplement=132

Angles/353763: Two angels are complementary and the measure of one angle is 40 degree less than the measure of the other. how many degrees are in each angle?
1 solutions

Answer 252877 by rfer(12645) on 2010-10-08 22:55:28 (Show Source):

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x+x-40=90
2x=130
x=65
x-40=25

sets-and-operations/353747: An electronics store surveyed every 7th customer who came into the store for a week.
Of the 350 people who responded,

144 people watched movies on VHS tapes.
239 people watched movies on DVDs.
54 people watched movies both on VHS tapes and DVDs.

Create a Venn diagram to reflect the above data, label your diagram clearly and submit to the W1: Assignment 4 Dropbox. Use your diagram to answer the following questions here.

i. Of those surveyed, how many watched only VHS tapes?
ii. Of those surveyed, how many watched only DVDs?
iii. Of those surveyed, how many watched VHS tapes or DVDs, but not both?
iv. Of those surveyed, how many watched VHS tapes or DVDs, or both?

1 solutions

Answer 252851 by rfer(12645) on 2010-10-08 20:52:41 (Show Source):

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1) 90
2) 185
3) 275
4) 329

Systems-of-equations/353724: I am trying to solve for the positive value of z
3x(1+y)=9+z where y=4, x=2
1 solutions

Answer 252843 by rfer(12645) on 2010-10-08 20:10:23 (Show Source):

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3*2(1+4)=9+z
3*10=9+z
30=9+z
z=21

Linear-equations/353725: I need help finding the slope and y-intercept for the equation 8x-3y=6
1 solutions

Answer 252842 by rfer(12645) on 2010-10-08 20:08:30 (Show Source):

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change to y int form
8x-3y=6
-3y=-8x+6
y=2 2/3x-2
y int=b=-2
(0,-2)

Travel_Word_Problems/353736: Two cars leave towns 800 kilometers apart at the same time and travel toward each other. One car's rate is 18 kilometers per hour less than the other's. If they meet in 5 hours, what is the rate of the slower car?
1 solutions

Answer 252841 by rfer(12645) on 2010-10-08 20:04:08 (Show Source):

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800/(2x-18)=5
800=5(2x-18)
800=10x-90
10x=890
x=89 kph
x-18=71 kph

expressions/353683: put parentheses in the
correct place in the expression to get the answer of 34 4+3x5-8+7 thank you
1 solutions

Answer 252818 by rfer(12645) on 2010-10-08 17:30:54 (Show Source):

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(4+3)(5)-8+7=34

Linear_Algebra/353444: Value of 6x if 3(x-4) + x = -2
1 solutions

Answer 252544 by rfer(12645) on 2010-10-07 21:28:25 (Show Source):

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3x-12+x=-2
4x=10
x=2.5
2.5*6=15

Average/353446: Mark took three tests. His grades were 74, 81 and 70. what grade must he get on the fourth test to receive an 80 average on the four tests?
1 solutions

Answer 252543 by rfer(12645) on 2010-10-07 21:26:10 (Show Source):

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(74+81+70+x)/4=80
225+x=80*4
225+x=320
x=95

Numeric_Fractions/353450: 2d+24+3d=84
I know the answer is d=12 but how do I show my work and work the problem ouT
1 solutions

Answer 252541 by rfer(12645) on 2010-10-07 21:23:57 (Show Source):

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5d=60
d=12

Average/353451: two times the quantity of three less than the number x is two more than the number.
1 solutions

Answer 252540 by rfer(12645) on 2010-10-07 21:22:49 (Show Source):

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2(x-3)=x+2
2x-6=x+2
x=8

Average/353453: The product of 12 and the quantity of 1 less than twice a number is 276, find the number.
1 solutions

Answer 252538 by rfer(12645) on 2010-10-07 21:20:40 (Show Source):

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12(2x-1)=276
24x-12=276
24x=288
x=12

Angles/353414: The measure of an angle is 3/4 the measure of its complement. Find the measure of the angle and its complement.
1 solutions

Answer 252509 by rfer(12645) on 2010-10-07 20:14:03 (Show Source):

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x+.75x=90
1.75x=90
x=51.43
.75x=38.57

Functions/353389: 4(x+5) - 5(2x-1) = x-24
1 solutions

Answer 252508 by rfer(12645) on 2010-10-07 20:10:16 (Show Source):

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4x+20-10x+5=x-24
-7x=-49
x=7

Linear-equations/353402: Show me the steps to graphing m=5,b=-4.
1 solutions

Answer 252505 by rfer(12645) on 2010-10-07 20:01:35 (Show Source):

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slope m=5
y int b=-4
plot y int first
(0,-4)
m=5 is the same as 5/1
rise over run
so from (o,-4) move one right and then four up for next point.

Distributive-associative-commutative-properties/353204: 4(3pq + 4r) + 5pq
1 solutions

Answer 252454 by rfer(12645) on 2010-10-07 16:57:51 (Show Source):

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17pq+16r

Numeric_Fractions/353263: What is: 5/6(4 1/5 * 3/7 - 1/2) + 1/2?
1 solutions

Answer 252453 by rfer(12645) on 2010-10-07 16:56:22 (Show Source):

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5/6(21/5*3/7-1/2)+1/2
5/6(63/35-1/2)+1/2
5/6(126/70-35/70+35/70)+1/2
5/6*63/35+1/2
315/210+105/210=410/210=1 20/21

Money_Word_Problems/353288: Donny decides to manufacture and sell his band’s CD. It requires an investment of $3349 for computer
hardware and it will cost $3.65 for materials for each disk. If each CD sells for $13.50, how many must he
sell to break even?
1 solutions

Answer 252451 by rfer(12645) on 2010-10-07 16:49:56 (Show Source):

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(3349+3.65x)/13.50x=
3349+3.65x=13.50x
3349=13.50x-3.65x
3349=9.85x
x=340

Numeric_Fractions/353280: Please help me solve this equation: 1/8 + 2/4 = ? I need a mixed number and a improper fraction as my answer and when I tried doing this equation I only got 5/8 so basically, how would I get a proper fraction to an improper fraction??

1 solutions

Answer 252450 by rfer(12645) on 2010-10-07 16:45:25 (Show Source):

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Your trying to be to creative.
1/8+4/8=5/8
I can't make it do more than that.

expressions/353285: Rom earned $12 one week and bought a radio for $8. The next week he earned $5. He went to the mall and spent $2 on lunch. Write an addition expressions for his earnings and expenses.
1 solutions

Answer 252449 by rfer(12645) on 2010-10-07 16:43:18 (Show Source):

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12-8+5-2=7 left

Graphs/353286: My problem is.
Ms.Makel is planning a breakfast meeting for 45 people. She wants at least one donut per person, but donuts are only sold in boxes of a dozen. What is the least number of boxes she should buy? I need help write and solve the problem.
Please and Thank You!!!!!!!!!!!
1 solutions

Answer 252447 by rfer(12645) on 2010-10-07 16:41:34 (Show Source):

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12= one doz
4*12=48
she needs 4 boxes

Linear-equations/353199: Word problem on percentage: Problem type 3
The price of a technology stock has dropped to 9.74 today. Yesterday's price was 9.85. Find the percentage decrease. Round your answer to the nearest tenth of a percent

1 solutions

Answer 252411 by rfer(12645) on 2010-10-07 15:18:48 (Show Source):

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.11/9.74=0.01129=01.1%

Linear-equations/353230: write this equation in standard form y=-7x+6
1 solutions

Answer 252407 by rfer(12645) on 2010-10-07 15:15:13 (Show Source):

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7x+y=6

Expressions-with-variables/353247: Solve the formulas below for the indicated variable. Show your work.
E/R+r =1, for R
I really don't even understand what they mean here, I'd really appreciate some help! Thank you!
1 solutions

Answer 252406 by rfer(12645) on 2010-10-07 15:14:15 (Show Source):

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E/R+r=1
E/R=1-r
R=E/(1-r)

Angles/352756: Two Angles are complementary. The Measure of the larger is 10 more than 4 times the measure of the smaller. Find the measure of each angle.
1 solutions

Answer 252141 by rfer(12645) on 2010-10-06 16:25:16 (Show Source):

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x+4x+10=180

Graphs/352334: 1. Nick worked 16 hours last week. He earned $5 per hour at a local restaurant and $5.50 per hour at a grocery store. If he earned a total of $82, how many hours did he work at the grocery store?
1 solutions

Answer 251821 by rfer(12645) on 2010-10-05 19:15:31 (Show Source):

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r+g=16
5r+5.5g=82
5r+5.5*(16-r)=82
5r+88-5.5r=82
-.5r=-6
r=12
g=4
---------------
5*12+5.5*4=
60+22=82

Equations/352333: how do you solve this problem.
5d=25
1 solutions

Answer 251820 by rfer(12645) on 2010-10-05 19:10:44 (Show Source):

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d=25/5
d=5

Expressions-with-variables/352338: how do you solve d squared minus 4d + 6 if d = -3
1 solutions

Answer 251819 by rfer(12645) on 2010-10-05 19:07:51 (Show Source):

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d^2-4d+6
-3^2-4*-3+6=
9+12+6=27

Permutations/352201: A survey of 51 pet owners revealed that 24 owned dogs, 28 owned cats, 11 owned turtles, 12 owned both dogs and cats, 7 owned both dogs and turtles, 3 owned both cats and turtles, and 2 owned all three. How many pet owners owned none of the following pets?
1 solutions

Answer 251818 by rfer(12645) on 2010-10-05 19:01:33 (Show Source):

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develope a Venn diagram.
The answer is 26

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Recent problems solved by 'rfer'