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Polynomials-and-rational-expressions/713268: -3(x+4)-5(x-4)


9/16-3/8+1/4

2(x-7)-5=5-(3-2x)
1 solutions

Answer 438347 by rfer(12678) About Me  on 2013-02-11 16:18:25 (Show Source):
You can put this solution on YOUR website!
-3x-12-5x+20=
-8x+8
---------------
9/16-6/16+4/16=7/16
------------------
2x-14-5=5-3+2x=21


Exponents-negative-and-fractional/713200: what is the rule between negative and positive exponents in a scientific notation multiplication or division problem? Can't remember which sign is taken, only remember that for x you add exponent and for / you subtract.
1 solutions

Answer 438324 by rfer(12678) About Me  on 2013-02-11 13:28:59 (Show Source):
You can put this solution on YOUR website!
You always give it the sign of the largest number.


Travel_Word_Problems/713209: joe leaves town at 1pm, marie leaves town at 2pm if marie travels 10mph faster than joe, how far from town will they be if marie catches joe at 7pm
1 solutions

Answer 438323 by rfer(12678) About Me  on 2013-02-11 13:26:42 (Show Source):
You can put this solution on YOUR website!
not enough info


test/713207: Find an equation of the linewith the given slope containing the given point (-7,3). Express your answer in slope-intercept form.
1 solutions

Answer 438322 by rfer(12678) About Me  on 2013-02-11 13:25:59 (Show Source):
You can put this solution on YOUR website!
not enough info.


test/713208: Find an equation of the line with the given slope containing the given point m=3 (-7,3). Express your answer in slope-intercept form.
1 solutions

Answer 438321 by rfer(12678) About Me  on 2013-02-11 13:25:06 (Show Source):
You can put this solution on YOUR website!
y=mx+b
3=3*-7+b
3=-21+b
24=b
---------------
y=3x+24


Equations/713050: When 9 is subtracted from a number and then divided by 2, the answer is 4. What is the number?
1 solutions

Answer 438267 by rfer(12678) About Me  on 2013-02-11 00:29:37 (Show Source):
You can put this solution on YOUR website!
(x-9)/2=4
x-9=8
x=17


Polynomials-and-rational-expressions/713027: how do you solve alberaic equations when there are fractions of 'X'?

1 solutions

Answer 438266 by rfer(12678) About Me  on 2013-02-11 00:27:45 (Show Source):
You can put this solution on YOUR website!
Work the fractions just like you always have.
Post a problem.


expressions/713052: 2a(a – 5) + 4(a – 5) how do I work this expression out to simplest form.

1 solutions

Answer 438265 by rfer(12678) About Me  on 2013-02-11 00:24:59 (Show Source):
You can put this solution on YOUR website!
2a^2-10a+4a-20=
2a^2-6a-20


Human-and-algebraic-language/713036: What is the translation of square of some number is equal to twice the number?
1 solutions

Answer 438257 by rfer(12678) About Me  on 2013-02-10 23:40:37 (Show Source):


Percentage-and-ratio-word-problems/713044: Erica bought 3 1/2 yards of fabric. If she uses 2/3 of the fabric to make a curtain, how much will she have left?
1 solutions

Answer 438256 by rfer(12678) About Me  on 2013-02-10 23:39:29 (Show Source):
You can put this solution on YOUR website!
7/2*1/3=7/6= 1 1/6 yds


Trigonometry-basics/712680: find the value of sin -120
1 solutions

Answer 438126 by rfer(12678) About Me  on 2013-02-10 12:30:58 (Show Source):


Equations/712719: Help please i did it but i don't know if it is right...thank you!
6(x-1)+2(4x+8)=3(4x+9)
this is my solution
6x-6+8x+16=12x+29
6x+8x-12=6-16+29
2x/2=19/2
x=9.5
1 solutions

Answer 438125 by rfer(12678) About Me  on 2013-02-10 12:29:01 (Show Source):
You can put this solution on YOUR website!
3*9=27
---------------
6x-6+8x+16=12x+27
14x+10=12x+27
14x-12x=27-10
2x=17
x=17/2
x=8.5


Linear-equations/712704: what is the slope of a line containing the point (0,-4) and (2,3)
1 solutions

Answer 438124 by rfer(12678) About Me  on 2013-02-10 12:25:15 (Show Source):
You can put this solution on YOUR website!
slope
m=(3--4)/(2-0)
m=7/2


Money_Word_Problems/712715: I need to find the total cost or sale price to the nearest cent.
I have no idea how to do it.
Here is the question:
$24.50 sandals, 20% discount.
1 solutions

Answer 438123 by rfer(12678) About Me  on 2013-02-10 12:19:51 (Show Source):
You can put this solution on YOUR website!
24.50*0.80=$19.60
---------------------
or
24.50*0.20=4.90
24.50-4.90=$19.60


test/712546: Two people spilt a restaurant bill equally, then one person added a $4.50 tip. The total amount if money paid was $23.80. What was each person's share of the bill before the tip was added? Why is the answer reasonable?
1 solutions

Answer 438034 by rfer(12678) About Me  on 2013-02-09 19:40:19 (Show Source):
You can put this solution on YOUR website!
(23.80-4.50)/2=$9.65


Exponents/712554: What is 7x to the 4th times 2x to the 4th
1 solutions

Answer 438031 by rfer(12678) About Me  on 2013-02-09 19:37:35 (Show Source):


test/712020: -17+3n=7(n-2)
1 solutions

Answer 437720 by rfer(12678) About Me  on 2013-02-07 23:53:23 (Show Source):
You can put this solution on YOUR website!
-17+3n=7n-14
-4n=3
n=-3/4


expressions/711984: 3(x-9>-18

1 solutions

Answer 437719 by rfer(12678) About Me  on 2013-02-07 23:51:39 (Show Source):
You can put this solution on YOUR website!
3x-27 > -18
3x > -18+27
3x > 9
x > 9/3
x > 3


Exponents/712004: what is the fact or form of x to the second power multiply by y to the second power plus 2xy
1 solutions

Answer 437718 by rfer(12678) About Me  on 2013-02-07 23:49:50 (Show Source):
You can put this solution on YOUR website!
(x^2)(y^2+2xy)
x^2y^2+2x^3y


Rectangles/712003: A field is 250 m by 310 m. A barn with floor dimensions of 21 m by 34 m is built in the field. How much field are is not covered by the barn?
1 solutions

Answer 437717 by rfer(12678) About Me  on 2013-02-07 23:46:48 (Show Source):
You can put this solution on YOUR website!
250*310=77500 sq m
21*34=714 sq m
77500-714=76,786 sq m


test/712030: I need help with some questions to my algerbra
1 solutions

Answer 437715 by rfer(12678) About Me  on 2013-02-07 23:41:30 (Show Source):


Radicals/712039: 3-7(2-5^2) solve this please
1 solutions

Answer 437714 by rfer(12678) About Me  on 2013-02-07 23:40:48 (Show Source):
You can put this solution on YOUR website!
3-7(2+25)
3-7(27)
3-189=-187


Angles/712042: my measure is four times my complementary what is my measure?
1 solutions

Answer 437713 by rfer(12678) About Me  on 2013-02-07 23:38:41 (Show Source):
You can put this solution on YOUR website!
x+4x=90
5x=90
x=90/5
x=18
4x=72


Equations/712050: Please help with this equation 5/2x+1=x+1/4 need to solve..thanks
1 solutions

Answer 437712 by rfer(12678) About Me  on 2013-02-07 23:36:36 (Show Source):
You can put this solution on YOUR website!
5/2x-2/2x=1/4-4/4
3/2x=-3/4
x=(-3/4)/(3/2)
x=-3/4*2/3
x=-6/12
x=-1/2


test/711494: (-5 minus square root of 3) ^2
1 solutions

Answer 437445 by rfer(12678) About Me  on 2013-02-06 22:43:54 (Show Source):
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(-5-1.732)^2
-6.732^2=45.32


test/711545: Cameron was given a bonus for having the highest sales in his company. He took 15% of his bonus and put it into savings. He put $ 2,100 in savings. How much was his bonus?
1 solutions

Answer 437444 by rfer(12678) About Me  on 2013-02-06 22:39:52 (Show Source):
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2100/0.15=$14,000


Age_Word_Problems/711495: A father is four times as old as his son and his daughter is five years younger than her brother. If their combined age is 73 years, find the age of each.
1 solutions

Answer 437443 by rfer(12678) About Me  on 2013-02-06 22:38:41 (Show Source):
You can put this solution on YOUR website!
x=son
4x=father
x-5=daughter
--------------
x+4x+x-5=73
6x=78
x=78/6
x=13
4x=52
x-5=8


Graphs/711513: Y=-1/4×-3/2
1 solutions

Answer 437441 by rfer(12678) About Me  on 2013-02-06 22:33:55 (Show Source):


Equations/711515: .05x+.15(50-x)=5.50
1 solutions

Answer 437440 by rfer(12678) About Me  on 2013-02-06 22:33:14 (Show Source):
You can put this solution on YOUR website!
0.05x+7.5-0.15x=5.5
-0.1x=5.5-7.5
-0.1x=-2
x=-2/-0.1x
x=20


percentage/711514: 135 is 108% of what number?
1 solutions

Answer 437439 by rfer(12678) About Me  on 2013-02-06 22:29:26 (Show Source):


test/711532: What percent tip did kenny leave for the waiter if the total bill was $50 and kenny gave the waiter $80 and told him to keep the change?
1 solutions

Answer 437436 by rfer(12678) About Me  on 2013-02-06 22:25:02 (Show Source):
You can put this solution on YOUR website!
30/50=0.60=60%