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Systems-of-equations/576686: Five more than 3 times a number is 41. What is the number?
1 solutions

Answer 369960 by rfer(12644) About Me  on 2012-02-22 21:26:51 (Show Source):
You can put this solution on YOUR website!
3x+5=41
3x=41-5
3x=36
x=36/3
x=12


Systems-of-equations/576685: Twice a number plus 4 times the same number is 42. What is the number?
1 solutions

Answer 369959 by rfer(12644) About Me  on 2012-02-22 21:25:45 (Show Source):
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2x+4x=42
6x=42
x=42/6
x=7


Linear_Equations_And_Systems_Word_Problems/576609: Ration of boys to girls is 9 to 4. you know there are 91 total students. How many of them are boys and how many girls? Thank you
1 solutions

Answer 369958 by rfer(12644) About Me  on 2012-02-22 21:23:59 (Show Source):
You can put this solution on YOUR website!
9x+4x=91
13x=91
x=7
9x=63 girls
4x=28 boys


Miscellaneous_Word_Problems/576610: If grass seed sells for $8 per pound and you spend $10, how much did you buy?
1 solutions

Answer 369956 by rfer(12644) About Me  on 2012-02-22 21:21:35 (Show Source):


Equations/576676: The difference between 8y and 3y is 45. Find the value of y
1 solutions

Answer 369954 by rfer(12644) About Me  on 2012-02-22 21:20:03 (Show Source):
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8y-3y=45
5y=45
y=45/5
y=9


Linear-equations/576675: What is 5x + 10 = 10y and 3y — 21 = 12x in "y =... " form? I don't get it. My email is chobbs985@gmail.com
Thanks
1 solutions

Answer 369953 by rfer(12644) About Me  on 2012-02-22 21:18:32 (Show Source):
You can put this solution on YOUR website!
I believe you want
y=0.5x+1
&
y=4x-7
-----------------
10y=5x+10
y=5/10x+10/10
y=0.5x+1
----------------
3y-21=12x
3y=12x+21
y=12x/3+21/3
y=4x+7


Triangles/576622: Find a formula for the length of the altitude to the hypotenuse of a right triangle whose legs have lengths of A and B.
1 solutions

Answer 369951 by rfer(12644) About Me  on 2012-02-22 21:14:25 (Show Source):
You can put this solution on YOUR website!
a^2+b^2=c^2
change to
c^2-a^2=b^2


Numbers_Word_Problems/576670: the sum of 5 times a number and four is nine. translate statement into equation and solve
1 solutions

Answer 369949 by rfer(12644) About Me  on 2012-02-22 21:11:58 (Show Source):
You can put this solution on YOUR website!
5x+4=9
5x=9-4
5x=5
x=5/5
x=1


Graphs/576642: find the y intercept of the graph of 2x +5y -10= 0
1 solutions

Answer 369948 by rfer(12644) About Me  on 2012-02-22 21:10:18 (Show Source):
You can put this solution on YOUR website!
2*0+5y=10
5y=10
y=2
(0,2)


Quadratic_Equations/576668: x^3=500
1 solutions

Answer 369945 by rfer(12644) About Me  on 2012-02-22 21:07:32 (Show Source):


real-numbers/576667: is 3.5 any of these?


Real Number
Rational Number
Irrational Number
Integer
Whole Number
Natural Number



1 solutions

Answer 369944 by rfer(12644) About Me  on 2012-02-22 21:06:34 (Show Source):
You can put this solution on YOUR website!
The first two.


Geometry_Word_Problems/576624: the width of recangle is 5 feet longer than one forth of its lenght. the perimeter is 80 feet. find its dimensions
1 solutions

Answer 369943 by rfer(12644) About Me  on 2012-02-22 21:03:29 (Show Source):
You can put this solution on YOUR website!
2x+2(0.25x+5)=80
2x+0.5x+10=80
2.5x=80-10
2.5x=70
x=70/2.5
x=28ft
0.25x+5=12ft


Graphs/576640: find the x intercept of the graph of 2x +5y -10= 0
1 solutions

Answer 369940 by rfer(12644) About Me  on 2012-02-22 20:59:12 (Show Source):
You can put this solution on YOUR website!
2x+5y-10=0
x inter is when y=0
2x+5*0-10=0
2x=10
x=10/2
x=5
(5,0)


Linear-equations/576639: Write the slope-intercept equation for the line that passes through (-4, 6) and (2, -6). Please show all of your work
1 solutions

Answer 369939 by rfer(12644) About Me  on 2012-02-22 20:55:41 (Show Source):
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m=(-6-6)/(2--4)
m=-12/6
m=-2
----------------
y=mx+b
-6=-2*2+b
-6=-4+b
-2=b
--------------
y=-2x-2


Equations/576657: Helping my grandson with 6th grade Algebra.
x+3x=x+x+10
How do I break down to get started in solving?

1 solutions

Answer 369937 by rfer(12644) About Me  on 2012-02-22 20:52:30 (Show Source):
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combine all of the "x"
x+3x=x+x+10
4x=2x+10
subtract 2x from each side
4x-2x=2x-2x+10
2x=10
divide both by 2
2x/2=10/2
x=5


Probability-and-statistics/576644: 7 - 3 4/9 = ?
1 solutions

Answer 369936 by rfer(12644) About Me  on 2012-02-22 20:50:06 (Show Source):
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6 9/9-3 4/9=3 5/9


Linear_Equations_And_Systems_Word_Problems/576645: the room numbers of two adjacent classrooms are two consecutive even numbers. If their sum is 654, find the classroom numbers.
1 solutions

Answer 369935 by rfer(12644) About Me  on 2012-02-22 20:48:56 (Show Source):
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654/2=327
326 and 328
---------------
or
x+x+2=654
2x=652
x=326
x+2=328


Triangles/576647: What is the hypotenuse of a right triangle if it's legs are 12cm and 16cm
1 solutions

Answer 369934 by rfer(12644) About Me  on 2012-02-22 20:46:02 (Show Source):
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c=20cm
a^2+b^2=c^2
sqrt c^2=20


Money_Word_Problems/572908: lets say if i invest 4200 for three years and earn 630 whats the simplest interest rate

1 solutions

Answer 368569 by rfer(12644) About Me  on 2012-02-14 21:52:44 (Show Source):
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I=Prt
630=4200*r*3
630=12600r
r=630/12600
r=0.05=5%


Radicals/572863: Im having a problem figuring out how to solve this equation. 3/2a-5=-1 rational expressions
1 solutions

Answer 368566 by rfer(12644) About Me  on 2012-02-14 21:50:15 (Show Source):
You can put this solution on YOUR website!
3/2a-5=-1
3/2a=-1+5
3/2a=4
3=4*2a
3=8a
a=3/8


Numbers_Word_Problems/572911: When 36 is subtracted from the square of a number, the result is 5 times the number. Find the negative solution.
1 solutions

Answer 368564 by rfer(12644) About Me  on 2012-02-14 21:46:34 (Show Source):
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x-36=5x
-36=4x
x=-36/4
x=-9


Angles/572918: find an angle which is 25 degree less then 4 times its complement.
1 solutions

Answer 368563 by rfer(12644) About Me  on 2012-02-14 21:44:50 (Show Source):
You can put this solution on YOUR website!
x+4x-25=90
5x=90+25
5x=115
x=23
4x-25=67


Money_Word_Problems/572434: please help. one thousand dollars are invested at 8% interest compound quarterlly. determine how much the investment is worth after 1year, 4years, and 7years
1 solutions

Answer 368418 by rfer(12644) About Me  on 2012-02-13 23:27:13 (Show Source):
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A=P(1+r/4)^(4*t)
A=1000(1+0.08/4)^(4*4)
A=1000(1.02)^16
A=1000*1.37279
A=$1372.79
You do the other two.
I did the 4yr one.


Geometry_Word_Problems/572451: How many square feet of surface are in one wall of a swimming pool 80ft long , 3ft deep at one end, and 16ft deep at the other?
1 solutions

Answer 368417 by rfer(12644) About Me  on 2012-02-13 23:11:22 (Show Source):
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make a triangle 80X13
figure that area.
(80*13)/2=520 sqft
---------------
a rectangle 3X80
3*80=240
---------------
total the two answers
520+240=760 sqft


Numbers_Word_Problems/572415: The sum of a number and three is less than nineteen less the number. What is this equation?
1 solutions

Answer 368416 by rfer(12644) About Me  on 2012-02-13 23:04:41 (Show Source):


Volume/572419: A storage trunk is 40 inches wide by 28 inches deep by 36 inches high what is the volume of the trunk
1 solutions

Answer 368415 by rfer(12644) About Me  on 2012-02-13 23:02:31 (Show Source):
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40*28*36=40,320 cu in


Numbers_Word_Problems/572428: Four times a number equal twenty









1 solutions

Answer 368414 by rfer(12644) About Me  on 2012-02-13 23:00:17 (Show Source):


Angles/572474: One angle is 20 more than its supplement. calculate both angle measures.
1 solutions

Answer 368412 by rfer(12644) About Me  on 2012-02-13 22:56:35 (Show Source):
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x+x+20=180
2x=180-20
2x=160
x=160/2
x=80
x+20=100


Angles/572477: One angle is 10 less than 3 times its supplement. Calculate both angles.
1 solutions

Answer 368410 by rfer(12644) About Me  on 2012-02-13 22:54:59 (Show Source):
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x+3x-10=180
4x=180+10
4x=190
x=190/4
x=47.5
3x-10=132.5


Numbers_Word_Problems/572359: 17 less than twice a number is -47. Find the number.
1 solutions

Answer 368383 by rfer(12644) About Me  on 2012-02-13 20:06:14 (Show Source):
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2x-17=-47
2x=-47+17
2x=-30
x=-30/2
x=-15


Rational-functions/572361: 2= 4/n + 1/3
1 solutions

Answer 368382 by rfer(12644) About Me  on 2012-02-13 20:03:31 (Show Source):
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2-1/3=4/n
5/3=4/n
5/3n=4
n=4/(5/3)
n=4*3/5
n=12/5
n=2 2/5