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Inequalities/468179: the smiths have saved $25,000 toward the purchase of a new car. if the sales tax if 5 % the purchase price of the smiths new car before
taxes cannot exceed what ?
1 solutions

Answer 321244 by rfer(12662) About Me  on 2011-07-07 20:39:00 (Show Source):
You can put this solution on YOUR website!
25000/1.05=$23,809.52


Coordinate-system/468174: graph: y=4x+80, y=1/2x+10
where do they intercept?
1 solutions

Answer 321241 by rfer(12662) About Me  on 2011-07-07 20:37:23 (Show Source):
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1/2x+10=4x+80
-3.5x=70
x=-20
-------------
y=4*-20+80
y=-80+80
y=0
-----------
intercept (-20,0)
----------------
0=1/5*-20+10


Inequalities/468176: a jewelry salesman can earn either a salary of 2,500 a month or
a salary of 1,000 a month plus 10% of all sales .how much does
he have to sell for the second choice to earn him more than the
first choice ?
1 solutions

Answer 321237 by rfer(12662) About Me  on 2011-07-07 20:30:43 (Show Source):
You can put this solution on YOUR website!
1500/0.1=$15,000


Functions/468159: Please I need hel

dipalma uivesity has a faculity reduction and lost 1/14 of its faculityu If 286 of it faculity was left after the reduction how many was there orginally.
1 solutions

Answer 321231 by rfer(12662) About Me  on 2011-07-07 20:00:09 (Show Source):
You can put this solution on YOUR website!
286/(13/14)=
286*14/13=308


Evaluation_Word_Problems/468071: The pitch of a roof is the ratio of the rise to the half-span. If a roof has a rise of 6 feet and a span of 30 feet, what is the pitch?

1 solutions

Answer 321213 by rfer(12662) About Me  on 2011-07-07 18:46:07 (Show Source):
You can put this solution on YOUR website!
6/30=1/5
one ft rise in five ft run


Systems-of-equations/468135: 2x+7-3x=-x+12
1 solutions

Answer 321211 by rfer(12662) About Me  on 2011-07-07 18:42:15 (Show Source):
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-x+x=5
no solution


Linear-systems/468082: i am having trouble solving equations. where can i get help to make them seem simple

1 solutions

Answer 321210 by rfer(12662) About Me  on 2011-07-07 18:40:21 (Show Source):
You can put this solution on YOUR website!
post a problem that we can see.


Systems-of-equations/468136: 3(x-1)+5=15x+7-4-4(3x+1)+3
1 solutions

Answer 321209 by rfer(12662) About Me  on 2011-07-07 18:39:30 (Show Source):
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3x-3+5=15x+7-4-12x-4+3
3x+2=3x+2
no solution


Linear-equations/467760: find the indicated outputs for f(x) - 5x^2 -3x.
I am having difficulty in trying to figure out this problem. I thought that it is five x to the second power which means five times five which would make it 25x minus 3x but the answer comes up incorrect. Could you please help me?
1 solutions

Answer 321018 by rfer(12662) About Me  on 2011-07-06 21:49:08 (Show Source):
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It says to use the indicated outputs, what are they?
If for example x=2
f(2)=-5*2^2-3*2
f(2)=-5*4-6
f(2)=-20-6
f(2)=-26
-----
Follow that example.


Polynomials-and-rational-expressions/467817: please help!! Divide. (x^2+4x-42)/(x+8)
1 solutions

Answer 321016 by rfer(12662) About Me  on 2011-07-06 21:44:03 (Show Source):


Radicals/467823: Find the length of the third side of the right triangle. Assume that c represents the length of the hypotenuse. Give an exact answer and, if appropriate, an approximation to three decimal places.
a = 3, b = 5, c = ?

1 solutions

Answer 321014 by rfer(12662) About Me  on 2011-07-06 21:37:51 (Show Source):
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9+25=34
sq rt 34=5.83 C


Expressions-with-variables/467820: Does the equation 3(x-1)+5=15x+7-4-4(3x+1)+3 has infinitely many solutions, one solution, or no solution?
1 solutions

Answer 321013 by rfer(12662) About Me  on 2011-07-06 21:36:00 (Show Source):
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3x-3+5=15x-4-12x-4+3
3x+2=3x+3
3x-3x=1
no solution


Percentage-and-ratio-word-problems/467782: If 21% of the group voted to change its bylaws and 19% voted against the change, how many people did not vote? The group has 1410 members. Thank you very much for your help
1 solutions

Answer 321011 by rfer(12662) About Me  on 2011-07-06 21:33:44 (Show Source):
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0.21+0.19=0.40 voted
1.00-.40=0.60 not voted
1410*0.6=846 did not vote


Equations/467735: Solve 126-a=-9a
1 solutions

Answer 320957 by rfer(12662) About Me  on 2011-07-06 19:10:42 (Show Source):
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8x=-126
x=-15.75


Money_Word_Problems/467736: . a. Solve for n: 2(n - 1) = 3(n + 5)
b. Find the zero of the function f(x)= 8 – 2x


1 solutions

Answer 320956 by rfer(12662) About Me  on 2011-07-06 19:09:33 (Show Source):
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A)
2n-2=3n+15
-n=17
n=-17
B)
(0,8)
(4,0)


Equations/467738: the odometer on Mr. Sweden's car read 36,345.8 mi. when he filled
up with gas . The next time he bought gas , it took 8.6 gal. to fill up and
he noticed his odometer read 36,504.9 mi . how many miles per gallon does
Mr. Sweden's car get ?
1 solutions

Answer 320955 by rfer(12662) About Me  on 2011-07-06 19:04:07 (Show Source):
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(36504.9-36345.8)/8.6=18.5 mpg


Angles/467740: Hello I am in need of help with a problem. The directions are, use a algebraic equation to find the measures of the two angles discribed. Begin by letting x represent the degree measure of the angle's complement or its supplement.
The measure of the angle is 81degrees more than twice that of its supplement.
I would really appreciate it if someone could help me. Thank you in advance
1 solutions

Answer 320954 by rfer(12662) About Me  on 2011-07-06 19:01:54 (Show Source):
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x+2x+81=180
3x=99
x=33
2x+81=147


Polynomials-and-rational-expressions/467743: omg! please help with these fractions!
(1/16x^4 + 3/7x^3 + 7/8x^2 +4) + (-9/16x^4 + 1/8x^2 -4)
1 solutions

Answer 320952 by rfer(12662) About Me  on 2011-07-06 18:59:05 (Show Source):
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=-1/2x^4+3/7x^3+x^2


Money_Word_Problems/467624: At his son's birth, a man invested $2,000 in savings at 6% for his son's college education. In 19 years, how much, approximately, will be available?

1 solutions

Answer 320882 by rfer(12662) About Me  on 2011-07-06 14:01:49 (Show Source):
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A=2000(1.06)^19
A=2000*3.0256
A=$6051.20


Triangles/467633: The sum of the measures of angles of a triangle are 180. If the largest angle is nine time larger than the smallest angle, and the third angle is 70 degrees larger than the smallest angle, find the measure of the angles
1 solutions

Answer 320881 by rfer(12662) About Me  on 2011-07-06 13:58:09 (Show Source):
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x+9x+x+70=180
11x=110
x=10
9x=90
x+70=80


Evaluation_Word_Problems/467634: Use scientific notation to divide the two numbers. Express answer using scientific notation; retain at least three decimal places. Please show all work.
(8.7•10^9)•(3.22•10^2)
1 solutions

Answer 320880 by rfer(12662) About Me  on 2011-07-06 13:56:05 (Show Source):
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=28.014x10^11
it becomes
=2.8014x10^12
multiply the numbers and add the exponents.


test/467636: Hi i need help with ny practice test that my teacher gave me and is big package and im doing " Percent Word Problems"
1.what percent of 126 is 22 ?
2. what percent of 137.4 is 96?
3.79.9 is 90% of what ?
4.73% of what is 156.4 ?
1 solutions

Answer 320879 by rfer(12662) About Me  on 2011-07-06 13:52:16 (Show Source):
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1)
22/126=0.175=17.5%
2)
96/137.4=0.70=70%
3)
79.9/0.90=88.78
4)
156.4/0.0473=3306.55


Travel_Word_Problems/467496: Traveling via car a total distance of 1698 miles to Tx. In order to reach our location in Tx within a time of 24 hours, what speed will we have to average? What speed will we have to travel in order to achieve the requested average?
1 solutions

Answer 320876 by rfer(12662) About Me  on 2011-07-06 13:29:18 (Show Source):
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1698/24=70.75 mph


Linear-equations/467448: Please help me with this algebra problem.
Given the equation y=2/7x + 3, find the y coordinates of (-7) (0) and (7) please show work and if you can please plot the points and graph the linear equation. I just can not get this one!
1 solutions

Answer 320744 by rfer(12662) About Me  on 2011-07-05 22:00:29 (Show Source):
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y=2/7*-7+3
y=-2+3
y=1
(-2,1)
-------------
y=2/7*0+3
y=3
(0,3)
------------
y=2/7*7+3
y=2+3
y=5
(7,5)


Miscellaneous_Word_Problems/467428: In a mixture of concret there are two pounds of cement mix for each pound of gravel if the mixture contains a total of 93 pounds of these two ingredients how many pounds of gravel ate ther
1 solutions

Answer 320738 by rfer(12662) About Me  on 2011-07-05 21:20:41 (Show Source):
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x+2x=93
3x=93
x=31# gravel
2x=62


Numbers_Word_Problems/466960: the sum of two consecutive even number is 26 what are the two numbers?

1 solutions

Answer 320359 by rfer(12662) About Me  on 2011-07-04 15:15:18 (Show Source):


Linear-systems/466968: i can't under stand if 3x+2y = -17
2x-5y = 14 the what is the process i can't under stand
what i need is Ex:
this i understand
X+2y=5
y=2x
X+2y=5
x+2(2x)= 5
x+4x=5
x+ 4= 5
5x and 5 divided by 5 y = 1 that i under stand but below i don't get it

THIS!!

Explanation:

Solving:
3x+2y = -17
2x-5y = 14

Using Substitution Method.
Expressing x as a function of y (from the first equation) x = (-17 -2y)/3
Substituting this expression into the second equation:
2(-17+2y)/3-5y = 14
Simplifying this expression:
(-19)y = 76
or
y = -4
Now, substituting y = -4 back into the x expressed as a function of y:
x = (-17-2y)/3 = -3


1 solutions

Answer 320358 by rfer(12662) About Me  on 2011-07-04 15:13:53 (Show Source):
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3x+2y=-17
2x-5y=14
2x=5y+14
x=2.5y+7
--------------
3*(2.5y+7)+2y=-17
7.5y+21+2y=-17
9.5y=-38
y=-4
-----------------
3x+2*-4=-17
3x-8=-17
3x=-9
x=-3
---------------
2*-3-5*-4=14
-6+20=14


Angles/466975: if the supplement of an angle is 10 less than thrice the complement of an angle, find the angle, its complement and supplement?
1 solutions

Answer 320353 by rfer(12662) About Me  on 2011-07-04 15:01:36 (Show Source):
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x+3x-10=90
4x=100
x=25 comp
3x-10=65 angle
180-65=115 sup


Travel_Word_Problems/467017: Hello,
I have a word problem on travel and distance.
Two cars are 400 miles apart. Both start at the same time and travel toward one another. They meet 4 hours later. If the speed of one car is 20 miles per hour faster than the other, what is the speed of each car?
Thank you
1 solutions

Answer 320350 by rfer(12662) About Me  on 2011-07-04 14:55:44 (Show Source):
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x+x+20=400/4
2x+20=100
2x=80
x=40 mph
x+20=60 mph


Geometric_formulas/466999: Hi I was hoping someone could help me with this problem! Thank you!! :)
Express in set-builder notation.
D = {5, 10, 15, 20,... }

1 solutions

Answer 320348 by rfer(12662) About Me  on 2011-07-04 14:53:49 (Show Source):
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{D|D IS MULTIPLE OF 5 BETWEEN 5 AND INFINITY}


Human-and-algebraic-language/467019: You invested 14,000 in two accounts paying 6% and 9% annual interest, respectively. If the total interest earned for the year $900, how much was invested at each rate?
1 solutions

Answer 320347 by rfer(12662) About Me  on 2011-07-04 14:51:38 (Show Source):
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0.06x+0.09(14000-x)=900
0.06x+1260-0.09x=900
-0.03x=-360
x=$12,000 at 6%
14000-12000=$2,000 at 9%