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expressions/265213: what is 4p-10+p+3p-p
1 solutions

Answer 195042 by rfer(12660) About Me  on 2010-02-03 18:40:29 (Show Source):
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4p-10+p+3p-p
7p-10


Linear_Equations_And_Systems_Word_Problems/265126: What is the concept of slope. Give an example of where it would be important to understand the significance of slope.
1 solutions

Answer 195031 by rfer(12660) About Me  on 2010-02-03 18:04:28 (Show Source):
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the slope of a roof
the slope of a highway


Miscellaneous_Word_Problems/265133: Jo needs an 85% average on her five math tests. She earned 99%, 85%, 79%, and 88% on her first four tests. What score must she earn on her fifth test in order to have an average of exactly 85% for all five tests?
1 solutions

Answer 195030 by rfer(12660) About Me  on 2010-02-03 18:02:43 (Show Source):
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(99+85+79+88+x)/5=85
351+x/5=85
351+x=85*5
351+x=425
x=74%


percentage/265177: Mr. hernandez had to interview a total of 63 households in his assignment. he haas already finished 28. What percentage of the households in his assignments has he finished? (Round your answer to the nearest tenth of a percent.)
1 solutions

Answer 195026 by rfer(12660) About Me  on 2010-02-03 17:58:08 (Show Source):
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28/63=.444=44.4%


Triangles/265174: Find the perimeter and area of a right triangle if one leg measures 40 mi. and the other leg measures 42 mi.
1 solutions

Answer 195025 by rfer(12660) About Me  on 2010-02-03 17:56:44 (Show Source):
You can put this solution on YOUR website!
C^2=A^2+B^2
c^2=40^2+42^2
c^2=1600+1764
C^2=3364
c=58 miles
--------------------
P=58+42+40
P=140 miles
----------------
A=.5lw
A=.5*42*40
A=840 sq miles


Volume/264475: In a 9 inch square cake pan and a 10 inch square cake pan, what is the difference in volume each pan will hold? Assume each pan is 2 inches high. Please show step by step work and include units with the solution.
Thank you..
1 solutions

Answer 194709 by rfer(12660) About Me  on 2010-02-02 12:17:11 (Show Source):
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v=lwh
9*9*2=162 cu in
10*10*2=200 cu in
200-162=38 cu in


Triangles/264459: Find the perimeter and area of a right trianlge if the shortest side is 24mm. and the longest side is 40mm. Please show me all the work and include the units.
Thanks so much...
1 solutions

Answer 194708 by rfer(12660) About Me  on 2010-02-02 12:14:28 (Show Source):
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A^2+B^2=C^2
24^2+40^2=C^2
c^2=576+1600
C^2=2176
c=46.65 mm
---------------------
46.65+40+24=110.65 mm
P=110.65 mm
----------------
A=(LW)/2
A=(40*24)/2
A=480 cu mm


Graphs/264468: If the y-coordinate of an ordered pair is 0, then the plotted point must be on the y-axis?
Graph:
a.)y=-3x+1

1 solutions

Answer 194702 by rfer(12660) About Me  on 2010-02-02 12:03:28 (Show Source):
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(0,1)
(1/3,0)


Linear-equations/264471: What is y=5x+4, (0,0)

1 solutions

Answer 194700 by rfer(12660) About Me  on 2010-02-02 12:01:45 (Show Source):
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the y int is (0,4),not (0,0)
slope=5


Polynomials-and-rational-expressions/264467: Simplify:
sqrt(12)sqrt(15)
1 solutions

Answer 194698 by rfer(12660) About Me  on 2010-02-02 11:59:46 (Show Source):
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sq rt 180=13.42


Circles/264463: How many cubic inches of air can a fully inflated basketball hold if it's radius is 3.8 inches? Give the solution accurate to the nearest hundredth and include the units for the solution.
Thank you...
1 solutions

Answer 194695 by rfer(12660) About Me  on 2010-02-02 11:57:11 (Show Source):
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v=4/3*3.14*3.8^3
v=229.73 cu in


Angles/264321: 10. Exactly how many cubic inches of air can a fully inflated basketball hold if its radius is 4.8 inches? Include correct units with your solution. Use "pi" for p.
1 solutions

Answer 194693 by rfer(12660) About Me  on 2010-02-02 11:55:10 (Show Source):
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v=4/3pir^3
v=4/3*3.14*4.8^3
v=463 cu in


Circles/264452: What is the exact area of a circle with a diameter of 25 inches?
1 solutions

Answer 194692 by rfer(12660) About Me  on 2010-02-02 11:50:48 (Show Source):
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A=pir^2
A=3.14*12.5^2
A=490.625 sq in


Graphs/264453: If the y-coordinate of an ordered pair is 0, then the plotted point must be on the y-axis?
Graph:
a.)y=-3x+1

1 solutions

Answer 194691 by rfer(12660) About Me  on 2010-02-02 11:48:54 (Show Source):
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y=-3x+1
0=-3x+1
3x=1
x=1/3
(1/3,0)
slope=-3
y int=1 (0,1)


Travel_Word_Problems/264332: He notices that at 10:45 a.m. they are passing a marker labeled 101, and at 11:00 a.m. the car reaches marker 119. what is the speed?
1 solutions

Answer 194607 by rfer(12660) About Me  on 2010-02-01 23:30:03 (Show Source):


Square-cubic-other-roots/264304: A semicircular window of radius 10 inches is to be laminated with a sunblock coating that costs $0.85 per square inch to apply. What is the total cost of coating the window, to the nearest cent?
(Use п = 3.14. Hint: Area of Circle: A = пr2)
How do I write the equation on questions like these? totally lost
1 solutions

Answer 194606 by rfer(12660) About Me  on 2010-02-01 23:27:55 (Show Source):
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A=1/2(3.14)(10)^2
A=157 sq in
157*.85=$133.45


Angles/264310: 9. How many cubic centimeters can a cigar box hold if its dimensions are 4 centimeters by 16 centimeters by 10 centimeters? Include correct units with your solution.
1 solutions

Answer 194605 by rfer(12660) About Me  on 2010-02-01 23:23:03 (Show Source):
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4*16*10=640 cu cm


Inequalities/264320: please help
solve the following equationor inequailty for the unknown variable.round answer to two decimal places if necessary.
10-x<4
1 solutions

Answer 194604 by rfer(12660) About Me  on 2010-02-01 23:20:25 (Show Source):
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10-x<4
-x<4-10
-x<-6
x>+6


Travel_Word_Problems/264287: The reeds are moving cross country. Mr reed leaves 3.5 hrs before mrs reed. If he averages 40 mph and she averages 75 mph, how long will it take mrs reed
to overtake mr reed?
1 solutions

Answer 194581 by rfer(12660) About Me  on 2010-02-01 21:23:24 (Show Source):
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leads by 3.5*40=140 miles
overtake speed is 35 mph
140/35=4 hrs


Quadratic_Equations/264182: 3r+6-9r=24
1 solutions

Answer 194537 by rfer(12660) About Me  on 2010-02-01 19:41:05 (Show Source):
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3r+6-9r=24
-6r=18
r=-3


Polynomials-and-rational-expressions/264191: multiply [3a-(2a-3)][3a+(2a-3)]
1 solutions

Answer 194535 by rfer(12660) About Me  on 2010-02-01 19:36:56 (Show Source):
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(3a-2a+3)(3a+2a-3)
(a+3)(5a-3)
5a^2-3a+15a-9
5a^2+12a-9


Linear-equations/264194: In which quadrant is the point (3,-14) located?
I or II or III or IV ?
Thank you for your help!
1 solutions

Answer 194533 by rfer(12660) About Me  on 2010-02-01 19:33:44 (Show Source):


Equations/263595: 3x+4+1/2(4x-1)=-3/2
1 solutions

Answer 194291 by rfer(12660) About Me  on 2010-01-31 20:30:37 (Show Source):
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3x+4+1/2(4x-1)=-3/2
3/1x+4/1+4/2x-1/2=-3/2
6/2x+8/2+4/2x-1/2=-3/2
10/2x=-10/2
x=-10/2*2/10
x=-20/20
x=-1


Linear-equations/263612: given the function of f described by f(x) =9x, find each of the following. f(-14),f(4), f(29)
1 solutions

Answer 194289 by rfer(12660) About Me  on 2010-01-31 20:24:35 (Show Source):
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f(x)=y
y=9x
-14=9x
x=-14/9
x=-1.56


Linear-equations/263617: Find the slope and the y-intercept
y=3x-2
The slope is ?
The y-intercept is (0,?)
5y + 2x + 8= 16+2x
Slope is?
y-intercept is 0,?
1 solutions

Answer 194287 by rfer(12660) About Me  on 2010-01-31 20:21:43 (Show Source):
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a)
slope=3
y int=(0,-2)
b)
5y+2x+8=16+2x
5y=8
y=8/5=1.6
slope=0
y int=(0,1.6)


Geometry_Word_Problems/263653: A farmer decides to enclose a rectangle garden,using the side of a barn as one side of the rectangle. What is the maximum area that the farmer can inclose with 60 ft of fence? What should the dimensions of the garden be to give this area?
1 solutions

Answer 194281 by rfer(12660) About Me  on 2010-01-31 20:14:18 (Show Source):
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a square of 15 ft by 15 ft


Permutations/263652: The number of building permits issued in a city this year was 72000. This represents 125% of last year's number of permits. How many building permits were issued last year?
1 solutions

Answer 194279 by rfer(12660) About Me  on 2010-01-31 20:12:32 (Show Source):
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72000/1.25=57600


Permutations/263649: A used car dealer estimates that 65% of the company's sales will occur on Thursday, Friday or Saturday. Using this estimate, how many cars out of the 80 sold last month were sold on Thursday, Friday or Saturday?
1 solutions

Answer 194276 by rfer(12660) About Me  on 2010-01-31 20:10:17 (Show Source):
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80*.65=52 cars


Probability-and-statistics/263647: The University of Metropolis requires its students to pass an examination in college-level mathematics before they can graduate. The students are given three chances to pass the exam; 61% pass it on their first attempt, 63% of those that take it a second time pass it then, and 42% of those that take it a third time pass it then.
What percent of the students are not allowed to graduate because of their performance on the exam? (Round the answer to the nearest whole number.)

1 solutions

Answer 194275 by rfer(12660) About Me  on 2010-01-31 20:08:34 (Show Source):
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61%+24.5%+9.8%=95.3=95% passed
5% did not pass
----------------
.39*.63=.245
.245*.42=.098


Graphs/263642: 5(3x+4)< or equal to 5x-10
1 solutions

Answer 194274 by rfer(12660) About Me  on 2010-01-31 20:03:30 (Show Source):
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5(3x+4)<=5x-10
15x+20<=5x-10
10x<=-30
x<=-3


Expressions-with-variables/263640: the strauss family is deciding between two lawn-care services. Green lawn charges a $49 start p fee, plus $29 per month. Grass team charges a $25 start up fee, plus $37 per month.
a: in how many months will both lawn-care servoces cost the same? what will that cost be?
b: if the family will use the service for only 6 months, which is the better option? explain.
1 solutions

Answer 194272 by rfer(12660) About Me  on 2010-01-31 20:00:45 (Show Source):
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49+29x=25+37x
8x=24
x=3 mo the prices equal
----------------------
49+29(6)=$223
----------------------
25+37(6)=$247