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Equations/61041: 4-3x=16 is the answer 4
dont get this one -13(3x-11)+2=28
6-4(2-1/2x)+x=22
help me please
1 solutions
Answer 41978 by checkley71(8403)   on 2006-11-12 20:40:50 (Show Source):
You can put this solution on YOUR website!4-3X=16
-3X=16-4
-3X=12
X-12/-3
X=-4
--------------------------------------
-13(3X-11)+2=28
-39X+143+2=28
-39X=28-2-143
-39X=-117
X=-117/-39
X=3
--------------------------------------------------------
6-4(2-1/2X)+X=22
6-8+2X+X=22
3X=22-6+8
3X=24
X=24/3
X=8
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Graphs/61049: Determine the equattion of each line. write teh answer in standard form using only intergers as the coefficients.
The line through (-2,4) that is perpendicular to the x-axis
1 solutions
Answer 41975 by checkley71(8403) on 2006-11-12 20:33:32 (Show Source):
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Miscellaneous_Word_Problems/61060: At 1:00 p.m., a car leaves a city and travels north at a rate of 55 mi/h. An hour later, a second car leaves the city and travels south at a rate of 60 mi/hr. At what time will the two cars be 285 miles apart?
1 solutions
Answer 41974 by checkley71(8403) on 2006-11-12 20:28:56 (Show Source):
You can put this solution on YOUR website!285=(55T)+60(T-1)
285=55T+60T-60
285=115T-60
115T=285+60
115T=345
T=345/115
T=3 HOURS THEY WILL BE 285 MILES APART
PROOF
285=55*3+60(3-1)
285=165+60*2
285=165+120
285=285
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Linear-systems/61020: Instructions: Solve each system by the elimination method.
What is the solution for 5x-y=5
-5x+2y=0
1 solutions
Answer 41946 by checkley71(8403) on 2006-11-12 17:18:12 (Show Source):
You can put this solution on YOUR website!5X-Y=5
-5X+2Y=0 ELIMINATE X BY ADDITION
---------------------------------------------
Y=5
THEN
5X-5=5
5X=10
X=2 SOLUTION
PROOF
5*2-Y=5
-Y=5-10
-Y=-5
Y=5 SOLUTION
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Rectangles/61017: I need help. I am lost on this algebra.
The area of a rectangle is 119 m2. The base is four less than three times the height. What is the length of the base?
1 solutions
Answer 41945 by checkley71(8403) on 2006-11-12 17:12:45 (Show Source):
You can put this solution on YOUR website!AREA=1/2BASE*HEIGHT
BASE=3*H-4
119=1/2(3*H-4)H
119=1/2(3H-4)H
119=1/2(3H^2-4H)
119=1.5H^2-2H
1.5H^2-2H-119=0 USING THE QUADRATIC EQUATION X=(-B+-SQRT[B^@-4AC])/2A WE GET
X=(2+-SQRT(4-4*1.5*-119])/2*1.5
X=(2+-SQRT[4+714])/3
X=(2+-SQRT[718])/3
X=(2+-26.8)/3
X=28.8/3
X=9.6 SOLUTION. THUS THE HEIGHT IS 9.6M
119=1/2(B*9.6)
119=9.6B/2
9.6B=2*119
9.6B=238
B=238/9.6
B=24.8 SOLUTION & THE LENGTH OF THE BASE.
PROOF
119=1/2(9.6*24.8)
119=1/2(238)
119=119
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Miscellaneous_Word_Problems/60890: One pipe can fill a tank in 8 minutes and a second pipe can fill it in 12 minutes. If the tank is empty, how long will it take both pipes to fill it?
Thank you for looking.
1 solutions
Answer 41942 by checkley71(8403) on 2006-11-12 16:51:13 (Show Source):
You can put this solution on YOUR website!TWODIFFERENT ITEMS WORKING TOGETHER TO ACCOMPLISH A TASK IS GIVEN BY
X*Y/(X+Y) THUS
8*12/(8+12)
96/20=4.8 MINUTES TO FILL THE TANK WHEN BOTH PIPES ARE USED
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Linear-systems/61015: A motorcycle manufacturer produces three different models: the Avalon, the Durango, and the Roadtripper. Production restrictions require it to make, on a monthly basis, 10 more Roadtrippers than the total of the other two models, and twice as many Durangos as Avalons. The shop must produce a total of 490 cycles per month. How many cycles of each type should be made per month?
I just don't know how to set it up!!!! Thanks in advance!
1 solutions
Answer 41941 by checkley71(8403) on 2006-11-12 16:46:58 (Show Source):
You can put this solution on YOUR website!A+D+R=490 GIVEN
R=10+(A+D) GIVEN
D=2A GIVEN
THEN R=10(A+2A) OR
R=10+(A+2A)
R=10+3A
THEN A+(2A)+(10+3A)=490
A+2A+10+3A=490
6A=490-10
6A=480
A=480/6
A=80 AVALONS
D=2*80
D=160 DURANGOS
R=10+(80+160)
R=10+240
PROOF
R=250
A+D+R=490
80+160+250=490
490=490
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Travel_Word_Problems/61006: If a boat goes downstream 72 miles in 3 hours and upstream 60 miles in 6 hours, the rate of the river and the rate of the boat in still water respectively are _______________? I have the answers, but want to know how to work it out, thanks.
1 solutions
Answer 41935 by checkley71(8403) on 2006-11-12 16:01:45 (Show Source):
You can put this solution on YOUR website!DISTANCE=RATE*TIME
72=3R OR R=72/3 OR R=24 MPH DOWNSTREAM
60=6R OR R=60/6 OR R=10 MPH UP STREAM
TO FIND THE CURRENT WE ONLY NEED TO FIND 1/2 THE DIFFERENCE IN THE TWOSPEEDSUP & DOWN STREAM THUS (24-10)/2=14/2=7 MPH FOR THE CURRENT
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Miscellaneous_Word_Problems/61004: This question is from textbook
Can somebody please help me!
Find all real and imaginary solutions, b^4 + 13b^2 + 36 = 0
I have been working on this problems for a couple of days and I can't seem to understand, or even know what to do. Thank you
1 solutions
Answer 41932 by checkley71(8403) on 2006-11-12 15:31:05 (Show Source):
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Geometry_Word_Problems/60957: A certain sum of money is invested at 10%. Twice that amount is invested at 8%. The total amount of interest from both investments is $91.00. How much is invested at 8%. Can you show me how you work it out and solve it?
1 solutions
Answer 41931 by checkley71(8403) on 2006-11-12 15:28:00 (Show Source):
You can put this solution on YOUR website!.10X+.08*2X=9100
.10X+.16X=9100
.26X=9100
X=9100/.26
X=35000 AMOUNT INVESTED @ 10%
2*35000=70000 INVESTED @ 8%
PROOF
35000*.10+70000*.08=9100
3500+5600=9100
9100=9100
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Travel_Word_Problems/60966: Ching leaves San Francisco and travels toward Los Angeles at 50 mi/h. An hour later, Phil leaves Los Angeles and travels toward San Francisco at 60 mi/h. If the two cities are 380 miles apart, how many hours will it take for Ching to meet Phil
1 solutions
Answer 41929 by checkley71(8403) on 2006-11-12 15:19:28 (Show Source):
You can put this solution on YOUR website!380=50H+60(H-1)
380=50H+60H-60
50H+60H=380+60
110H=440
H=440/110
H=4 HOURS AFTER CHING LEFT THEY MEET
PROOF
380=50*4+60(4-1)
380=200+60*3
380=200+180
380=380
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Evaluation_Word_Problems/60967: Sally bought three chocolate bars and a pack of gum and paid $1.75. Jake bought two chocolate bars and four packs of gum and paid $2.00. Find the cost of a chocolate bar and the cost of a pack of gum.
1 solutions
Answer 41928 by checkley71(8403) on 2006-11-12 15:11:59 (Show Source):
You can put this solution on YOUR website!3B+G=175 OR G=175-3B
2B+4G=200 NOW SUBSTITUTE (175-3B) FOR G IN THE SECOND EQUATION WE GET
2B+4(175-3B)=200
2B+700-12B=200
-10B=-500
B=-500/-10
B=50 SOLUTION ($.50 FOR THE BARS)
G=175-3*50
G=175-150
G=25 SOLUTION ($.25 FOR THE GUM)
PROOF
2*50+4*25=200
100+100=200
200=200
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Polynomials-and-rational-expressions/60976: 1.) solve the following system by elimination
2x-4y=7
x-y=9
2.) the sum of two intergers, a and b (a>b), is 1,000. the smaller minus the larger
is -746. find the value of the intergers a and b.
3.) factor completely.
(a) w^3 - 1,000
(b) (w - x)^3 + z^3
4.) factor completely.
c^2 - 1
1 solutions
Answer 41927 by checkley71(8403) on 2006-11-12 15:04:56 (Show Source):
You can put this solution on YOUR website!x-y=9 or x=y+9 then
2(y+9)-4y=7
2y+18-4y=7
-2y=7-18
-2y=-11
y=-11/-2
y=5.5 solution
then
x=5.5+9
x=14.5 solution
proof
2*14.5-4*5.5=7
29-22=7
7=7
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Expressions-with-variables/60997: Roland traveled from Nashville to St. Louis, a distance of 300 miles. If he had increased his speed by 10 mph he would have arrived at St. Louis an hour and 30 minutes sooner. What was his speed?
1 solutions
Answer 41925 by checkley71(8403) on 2006-11-12 14:57:17 (Show Source):
You can put this solution on YOUR website!300=rt or r=300/t
300=(r+10)(t-1.5) now substitute (300/t) for r in the second equation we get
300=(300/t+10)(t-1.5)
300=(300/t*t)+10*t+(300/t*-1.5)+(10*-1.5)
300=300+10t-450/t-15
0=10t-450/t-15
0=(10t^2-450-15t)/t
0=10t^2-15t-450
(5t+30)(2t-15)=0
5t+30=0
5t=-30
t=-30/5
t=-6
2t-15=0
2t=15
t=15/2
t=7.5 hours then
300=r*7.5
r=300/7.5
r=40 mph speed of trip
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Linear-systems/61001: This question is from textbook Algebra 1
Evaluate the function for the given value of x. then graph the function.
29. f(x)=x-7 when x=-2
30. f(x)=-x+4 when x=4
31. f(x)=2x+6 when x=-3
32. f(x)=1.5x-42 when x=-9
1 solutions
Answer 41922 by checkley71(8403) on 2006-11-12 14:26:23 (Show Source):
You can put this solution on YOUR website!f(x)=x-7 x=-2 f(-2)=-2-7 f(-2)=-9
f(x)=-x+4 x=4 f(4)=-4+4 f(4)=0
f(x)=2x+6 x=-3 f(-3)=2*-3+6 f(-3)=-6+6 f(-3)=0
f(x)=1.5x-42 x=-9 f(-9)=1.5*-9-42 f(-9)=-13.5-42 f(-9)=-55.5
-----------------------------------------------------------------------------
sorry -- don't have graphing capabilities.
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Linear-systems/60950: Instructions: Solve each system by the substitution method.
What is the solution for 6x+9y=6
2x=2-3y
1 solutions
Answer 41892 by checkley71(8403) on 2006-11-11 22:17:09 (Show Source):
You can put this solution on YOUR website!6x+9y=6
6x=6-9y
x=6/6-9y/6
x=1-3y/2 substitute (1-3y/2) for z in the other equation
6*(1-3y/2)=6-9y
6-18y/2=6-9y
6-9y=6-9y
0=0 no solutions other than x & y=0
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Mixture_Word_Problems/60952: Mardi received an inheritance of $50,000. She invested part at 8% and deposited the remainder in tax-free bonds at 12%. Her total annual income from the investments was $4,800. What amount was invested at 8%?
1 solutions
Answer 41889 by checkley71(8403) on 2006-11-11 22:08:19 (Show Source):
You can put this solution on YOUR website!.08x+.12(50000-x)=4800
.08x+6000-.12x=4800
-.04x=4800-6000
-.04x=-1200
x=-1200/.04
x=30000 invested @ 8%
proof
.08*30000+.12*20000=4800
2400+2400=4800
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Money_Word_Problems/60948: I seem to have trouble when I am setting up for two unknowns. Can anyone help?
Six cans of soda and two candy bars cost $5.12. At the same prices, 8 cans of soda and 5 candy bars cost $9.86. Find the price per can of soda and price per candy bar.
Thanks for your efforts.
1 solutions
Answer 41888 by checkley71(8403) on 2006-11-11 21:53:37 (Show Source):
You can put this solution on YOUR website!6s+2b=512
8s+5b=986
------------------ multiply equation 1 by -2.5 & add to the second equation
-15s-5b=-1280
8s+5b=986
------------------
-7s=-294
s=-294/-7
s=42
------------------
6*42+2b=512
252+2b=512
2b=512-252
2b=260
b=260/2
b=130
proof
8*42+5*130=986
336+650=986
986=986
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Expressions-with-variables/60945: Can anyone help getting this set up and solved? Thanks
Solve 5x^2 + 2x - 1 = 0
Thanks!
1 solutions
Answer 41881 by checkley71(8403) on 2006-11-11 21:36:00 (Show Source):
You can put this solution on YOUR website!5x^2+2x-1=0 using the quadratic equation we get
x=(-b+-sqrt[b^2-4ac])/2a
x=(-2+-sqrt[4-4*5*-1])/2*5
x=(-2+-sqrt[4+20])/10
x=(-2+-sqrt24)/10
x=(-2+-4.9)/10
x=(-2+4.9/10
x=2.9/10
x=.29 solution
x=(-2-4.9)/10
x=-6.9/10
x=-.69 solution
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Quadratic_Equations/60937: A garden area is 30 ft long and 20ft wide. A path of uniform width is set around the edge. If the remaining garden area is 400ft^2, what is the width of the path?
1 solutions
Answer 41876 by checkley71(8403) on 2006-11-11 20:57:40 (Show Source):
You can put this solution on YOUR website!(30-2x)(20-2x)=400
600-40x-60x+4x^2=400
4x^2-100x+600-400=0
4x^2-100x+200=0
x^2-25x+50=0
using the quadratic equation x=(-b+-sqrt[b^2-4ac])/2a we get
x=(-25+-sqrt[625-4*1*50])/2*1
x=(-25+-sqrt[625-200])/2
x=(-25+-sqrt425)/2
x=(-25+-20.6)/2
x=(-25+20.6)/2
x=-4.4/2
x=-2.2 solution
x=(-25-20.6)/2
x=-45.6/2
x=-22.8 solution
seeing as one of these sidesare only 20 ft we can ignore this solution
proof using the first soluition we get
(30-2*2.2)+(20-2*2.2)=400
(30-4.4)(20-4.4)=400
25.6*15.6=400
400=400
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Inequalities/60906: In which quadrants does the graph of the following inequality lie? 2x - y <= 4
a) I,II only
b) I,II,III only
c) I,III,IV only
d) I,II,III,IV
e) none of these
1 solutions
Answer 41874 by checkley71(8403) on 2006-11-11 18:29:19 (Show Source):
You can put this solution on YOUR website!2X-Y<=4
-Y=2X+4
Y=-2X-4 THEN THE Y INTERCEPT IS (0,-4)SETTING Y=0 WE FIND THE VALUE OF X
0=2X+4
2X=-4
X=-4/2
X=-2 OR (-2,0)
ANSWER D) NONE OF THE ABOVE.
THIS LINE FALLS WITH QUADRANTS II,III,& IV ONLY.
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Linear-systems/60922: This question is from textbook beginning algebra
21. 3x+5y=15
23. -4x+3y=12
25. x-7y=3 I am not sure how to solve with 2 variables. please help me!!!
1 solutions
Answer 41873 by checkley71(8403) on 2006-11-11 18:11:23 (Show Source):
You can put this solution on YOUR website!ONE EQUATION WITH TWO VARIABLES CANNOT BE UNIGUELY SOLVED BECAUSE
THERE ARE MANY DIFFERWENT COMBINATIONS OF VALUES FOR EACH VARIABLE.
EXAMPLE 3X+5Y=15 IF X=5 THEN Y=0 OR IF X=0 THEN Y=3
IF YOUR TRYING TO SOLVE FOR X OR Y THE
3X+5Y=15
3X=15-5Y
X=15/3-5Y/3
X=5-5Y/3
OR SOLVING FOR Y THEN
3X+5Y=15
5Y=15-3X
Y=15/5-3X/5
Y=3-3X/5
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Square-cubic-other-roots/60912: I am really having difficulty understanding this section of my algebra class.
Solve:
SQRT(3X+5)= SQRT(5X-7)
Can anyone show me the steps the solve this?
1 solutions
Answer 41863 by checkley71(8403) on 2006-11-11 15:03:23 (Show Source):
You can put this solution on YOUR website!ignore the sqrt signs as the numbers under the radicals are equal thus --
3x+5=5x-7
3x-5x=-7-5
-2x=-12
x=-12/-2
x=6
proof
3*6+5=5*6-7
18+5=30-7
23=23
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Quadratic_Equations/60913: Please, please help with this question. I do not know where to go.
When a ball is thrown vertically upward, its height (h, in feet) above the ground after t seconds is described by the mathematical formula h = - 16t2 + 96t + 80. At what times is the ball 103 feet above the ground?
1 solutions
Answer 41862 by checkley71(8403) on 2006-11-11 14:58:46 (Show Source):
You can put this solution on YOUR website!103=-16t^2+96t+80
16t^2-96t-80+103=0
16t^2-96t+23=0
(4x-23)(4x-1)=0
4x-23=0
4x=23
x=23/4
x=5.75 solution 5.75 seconds
4x-1=0
4x=1
x=1/4
x=.25 solution .25 seconds
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