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Polynomials-and-rational-expressions/233301: P dollars is invested at annual interest rate r for 1 year. If the interest is compounded semiannually, then the polynomial P(1+r/2)^2 represents the value of the investment after one year. Rewrite this expression without parentheses. Evaluate the polynomial if P=$200 and r= 10%.
1 solutions

Answer 172213 by rfer(12670) About Me  on 2009-10-30 18:08:48 (Show Source):
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A=200*1.05^2
A=200*1.1025
A=$220.50


expressions/233318: -2x+4=5-3x
1 solutions

Answer 172212 by rfer(12670) About Me  on 2009-10-30 18:03:56 (Show Source):
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-2x+4=5-3x
x=1


Equations/233312: 40-0.2Q=0.2Q
1 solutions

Answer 172206 by rfer(12670) About Me  on 2009-10-30 17:04:46 (Show Source):
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40-0.2q=0.2q
40=0.4q
q=100


Inverses/233247: Solve for t
w=a^2/t
1 solutions

Answer 172174 by rfer(12670) About Me  on 2009-10-30 12:34:37 (Show Source):
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t=a^2/w
t times w equals a^2
so divide either into a^2


Linear-equations/232533: point slope form of the line that passes through (4,-1) with the slope of two
1 solutions

Answer 172172 by rfer(12670) About Me  on 2009-10-30 12:21:35 (Show Source):
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y-y1=m(x-x1)
y-(-1)=2(x-4)
y+1=2x-8
y=2x-9


Triangles/233201: if a particular right triangle has two equial side, this would be >>> - a 30-60-90 right triangle, b 45 degree right triangel, c 40-50 right triangle, or d 20-70 right triangle. thanks
1 solutions

Answer 172161 by rfer(12670) About Me  on 2009-10-30 11:50:36 (Show Source):
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b) an equilateral triangle


Angles/233236: The Measure Of A Angle Is 18 Less Than Twice Its Complement. Find The Measure Of The Angle.
1 solutions

Answer 172159 by rfer(12670) About Me  on 2009-10-30 11:46:57 (Show Source):
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x+2x-18=90
3x=108
x=36
2x-18=54


Equations/233073: the perimeter of a pool table is 30ft. the table is twice as long as it is wide.what is the length of the pool table.
1 solutions

Answer 172110 by rfer(12670) About Me  on 2009-10-29 23:06:37 (Show Source):
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P=2w+2L
30=2w+2(2w)
30=6
w=5ft
L=10ft


Equations/233075: victoria weight 5/7 as much as mario. victoria weights 125bl.how much does mario weight?
1 solutions

Answer 172109 by rfer(12670) About Me  on 2009-10-29 23:03:06 (Show Source):
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5/7=125/x
cross multiply
5x=875
x=175 lbs mario


percentage/233077: what percent of 88.6 is 70?
1 solutions

Answer 172108 by rfer(12670) About Me  on 2009-10-29 22:58:46 (Show Source):
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70/88.6=.79=79%


Polynomials-and-rational-expressions/233088: Solve.
-(x+8)=3(2x-4)
1 solutions

Answer 172107 by rfer(12670) About Me  on 2009-10-29 22:52:35 (Show Source):
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-(x-8)=3(2x-4)
-x+8=6x-12
-7x=-20
x=20/7=2 6/7


Linear-equations/233026: what is the slope and y intercept of this equation
5x-2y=10
y=-5??


slope= -5/-2 ????
1 solutions

Answer 172071 by rfer(12670) About Me  on 2009-10-29 19:40:00 (Show Source):
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5x-2y=10
-2y=-5x+10
y=5/2x-10
y=mx+b
m=slope=5/2
b=-10
(0,-10)
remember when multiplying or dividing by to negative numbers the results is positive.


Inequalities/232967: 5x+24=2x+15
1 solutions

Answer 172054 by rfer(12670) About Me  on 2009-10-29 18:29:52 (Show Source):
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5x+24=2x+15
3x=-9
x=-3


Functions/232981: A photographer charges a sitting fee of$15 plus $3 for each pose. Write a function to describe the situation.
1 solutions

Answer 172053 by rfer(12670) About Me  on 2009-10-29 18:27:13 (Show Source):


Signed-numbers/232911: can you help me solve this -14
-23
1 solutions

Answer 172048 by rfer(12670) About Me  on 2009-10-29 17:55:04 (Show Source):


Proportions/232920: find the value of x.
6x-2 over 7 = 5x+7 over 8
1 solutions

Answer 172046 by rfer(12670) About Me  on 2009-10-29 17:53:14 (Show Source):
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6x-2/7=5x+7/8
8*(6x-2)=7*(5x+7)
48x-16=35x+49
13x=65
x=5


Miscellaneous_Word_Problems/232916: For every 1 hour parked or part of, there is a 1.00 charge for parking or any part of an hour. There is a $5.00 daily Maximum

1. Customer arrives at 9:15 am Total time parked hrs mins
Customer departs at 11:30 am Total parking charge


1 solutions

Answer 172044 by rfer(12670) About Me  on 2009-10-29 17:45:53 (Show Source):
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2.25 hrs * $1 per hr=$2.25


Polynomials-and-rational-expressions/232917: 12(2x+1)=9(2x-5)+27
1 solutions

Answer 172043 by rfer(12670) About Me  on 2009-10-29 17:42:48 (Show Source):
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12(2x+1)=9(2x-5)+27
24x+12=18x-45+27
combine like terms
6x=30
x=5


Linear-equations/232949: can you help me figure out this linear equation and help me graph it.
y=-2/3x+5
1 solutions

Answer 172040 by rfer(12670) About Me  on 2009-10-29 17:38:18 (Show Source):
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y=-2/3x+5
y=-2/3(0)+5
y=5
(0,5)
--------------
2/3x=-y+5
2/3x=-0+5
2/3x=5x=5*3/2
x=15/2
x=7 1/2
(7 1/2,0)
There is a start for you


Inequalities/232950: three new ink cartridges cast $9 less than 5 new ink cartridges. Write and solve an equation to find the cost of each ink cartidges.

1 solutions

Answer 172036 by rfer(12670) About Me  on 2009-10-29 17:33:32 (Show Source):
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3x-9=5x
2x=9
x=$4.50 ea


Vectors/232927: solve by substitution 4x+5y= -9
-2x+y=15 what is the solution set , I came up with (-2,4) am I right
1 solutions

Answer 172017 by rfer(12670) About Me  on 2009-10-29 16:38:23 (Show Source):
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Give it another try.
The answer is (-6,3)


Mixture_Word_Problems/232862: a motel charges 80.00 per day for double occupancy and 70.00 per day for single occupancy. If 80 rooms are occupied one night for a total of 5800.00 how many rooms of each kind are occupied?
1 solutions

Answer 171993 by rfer(12670) About Me  on 2009-10-29 14:29:20 (Show Source):
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d+s=80, d=80-s
80d+70s=5800
80(80-s)+70s=5800
6400-80s+70s=5800
-10s=-600
s=60
d=20


Exponents/232872: 1.Solve using the five-step problem-solving process. Show all steps necessary to arrive at your solution. Express the answer in scientific notation to two decimals places unless requested otherwise.
If the distance from the earth to the sun were 92,900,000 miles, how long would it take a rocket, traveling at 2.8 × 103 miles per hour, to reach the sun? (Round to three places)


2.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)



3.A square light-switch plate is made which measures 6 inches on each side. A square hole measuring 1 inch on each side is left in the center. If the cost to construct the plate is $3.50 per square inch, what is the construction cost? (Hint: Use A = s2)


4.A cylindrical drum has a diameter of 3 feet and a volume of 45 cubic feet. What is the height of the drum? (Hint: Use V = пr2h)


1 solutions

Answer 171990 by rfer(12670) About Me  on 2009-10-29 14:20:26 (Show Source):
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2)
A=(pir^2)/2
A=3.14*10^2/2
A=157 sq in
3)
A=s^2-1^2
A=6^2-1^2
A=36-1
A=35
35*3.5=$122.50
4)
V=pir^2h
h=V/pir^2
h=45/3.14*1.5^2
h=45/7.065
h=6.37 ft


Linear-equations/232887: through:(3,5), slope=5/3

1 solutions

Answer 171986 by rfer(12670) About Me  on 2009-10-29 14:08:59 (Show Source):
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y=mx+b
y=5/3x
b=0
(0,0)


Travel_Word_Problems/232869: an airplane and a jet aircraft cross each other at different altitudes traveling in opposite directions the jet travels 5 times the rate of the airplane. In 3 hours they are 1620 miles apart. find the speed of each aircraft.
1 solutions

Answer 171984 by rfer(12670) About Me  on 2009-10-29 14:07:05 (Show Source):
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3(5x+x)=1620
15x+3x=1620
18x=1620
x=90 mph
5x=450 mph


Triangles/232771: A right triangle has a hypotenuse c=12.6 and a leg b=8.5. What does leg a approximately equal?
1 solutions

Answer 171935 by rfer(12670) About Me  on 2009-10-29 02:06:08 (Show Source):
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c^2=a^2+b^2
12.6^2-8.5^2=a^2
158.76-72.25=86.51
sq rt of 86.51=9.3


decimal-numbers/232768: How do I solve this equation:
x - 0.25x = 72
1 solutions

Answer 171934 by rfer(12670) About Me  on 2009-10-29 02:02:43 (Show Source):
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x-0.25x=72
0.75x=72
x=96


Polynomials-and-rational-expressions/232686: 3d-8=-6+d wats the answer
1 solutions

Answer 171925 by rfer(12670) About Me  on 2009-10-28 23:39:53 (Show Source):
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3d-8=-6+d
2d=2
d=1


Equations/232698: A copy center offers its customers two different pricing plans for black and white photocopies of 8.5 in. by 11 in. pages. Customers can either pay 8 cents per page or 7.50 for a discount card the lowers the cost to 5 cents per page. Write and solve an equation to find the number of photocopies for which the cost of each plan is the same.
1 solutions

Answer 171924 by rfer(12670) About Me  on 2009-10-28 23:37:17 (Show Source):
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.08x=7.5+.05x
.03x=7.5
x=250 copies


decimal-numbers/232700: Algebra: What is decimal form of 7/12?
1 solutions

Answer 171923 by rfer(12670) About Me  on 2009-10-28 23:34:25 (Show Source):
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7/12=0.58333333
divide 7 by 12


Circles/232710: a ball has radius of 10 inches. find the surface area. leave the answer in terms of pie.
1 solutions

Answer 171921 by rfer(12670) About Me  on 2009-10-28 23:32:49 (Show Source):
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A=4pir^2
A=4(3.14)(10)^2