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Travel_Word_Problems/207950: A certain aircraft can fly 960 miles with the wind in 4 hours and travel the same distance against the wind in 6 hours. What is the speed of the wind? 1 solutions
Answer 157288 by checkley77(12569) on 2009-08-22 19:08:09 (Show Source):
You can put this solution on YOUR website!D=RT
T=D/R
4=960/R
4R=960
R=960/4
R=240MPH WITH THE WIND
6=960/R
6R=960
R=960/6
R=160 MPH AGAINST THE WIND.
(240-160)/2=80/2=40 MPH IS THE WIND SPEED.
PROOF:
240*4=160*6
960=960
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Graphs/207956: I need help with this question.
Solve using either elimination or substitution. If the system has either no solution or an infinite number of solutions, state this.
7x - 2y = 24
5x + 4y = 28 1 solutions
Answer 157285 by checkley77(12569) on 2009-08-22 19:00:06 (Show Source):
You can put this solution on YOUR website!7x - 2y = 24 MULTIPLY THIS EQUATION BY 2 & ADD THEM.
5x+4y=28
14X-4Y=48
---------------------
19X=76
X=76/19
X=4 ANS.
7*4-2Y=24
28-2Y=24
-3Y=24-28
-2Y=-4
Y=-4/-2
Y=2 ANS.
PROOF:
5*4+4*2=28
20+8=28
28=28
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Numbers_Word_Problems/207809: You are selling tickets at a high school football game. Student tickets cost $2 and general admission tickets cost $3. you sell 1957 tickets and collect $5035. How many of each ticket did you sell? 1 solutions
Answer 157213 by checkley77(12569) on 2009-08-21 21:13:05 (Show Source):
You can put this solution on YOUR website!2s+3g=5035
s+g=1957
s=1957-g
2(1957-g)+3g=5035
3914-2g+3g=5035
g=5035-3914
g=1121 general tickets sold.
1957-1121=836 student tickets sold.
Proof:
2*836+3*1121=5035
1672+3363=5035
5035=5035
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Equations/207842: solve system using addition method
-4x+y=4
-16x-4y=16
solution (?,?) 1 solutions
Answer 157204 by checkley77(12569) on 2009-08-21 20:43:41 (Show Source):
You can put this solution on YOUR website!-4x+y=4 multiply by 4 & add
-16x-4y=16
-16x+4y=16
--------------------
-32y=32
y=32/-32
y=-1 ans.
-4x-1=4
-4x=4+1
-4x=5
x=5/-4
x=-5/4ans.
solution (-5/4,-1)
Proof:
-16*(-5/4)+4*-1=16
80/4-4=16
20-4=16
16=16
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Equations/207844: i do not know what to do on this problem.
How much 40% antifreeze solution must be mixed with a 80% antifreeze solution to produce 20 gallons of a 70% disinfectant solution? Round answer to the nearest gallon.
? gallons 40% solution, ? gallons 80% solution 1 solutions
Answer 157203 by checkley77(12569) on 2009-08-21 20:33:43 (Show Source):
You can put this solution on YOUR website!.40x+.80(20-x)=.70*20
.40x+16-.80x=14
-.40x=14-16
-.40x=-2
x=-2/.40
x=5 gal of 40% antifreeze is used.
20-5=15 gal of 80% anti freeze is used.
[5] gallons 40% solution, [15] gallons 80% solution
Proof:
.4*5+.8*15=.7*20
2+12=14
14=14
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Equations/207843: I think this is linear equations in 2 variables....
3v+2d=33.07
6v+6d=79.38
v=?,d=? 1 solutions
Answer 157202 by checkley77(12569) on 2009-08-21 20:27:28 (Show Source):
You can put this solution on YOUR website!3v+2d=33.07 muktiply this equation by -2 & add
6v+6d=79.38
-6v-4d=-66.14
------------------
2d=13.24
d=13.24/2
d=6.62 ans.
3v+2*6.62=33.07
3v+13.24=33.07
3v=33.07-13.24
3v=19.83
v=19.83/3
v=6.61 ans.
Proof:
6*6.61+6*6.62=79.38
39.66+39.72=79.38
79.38=79.38
----------------------
v=6.61,d=6.62
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Linear_Equations_And_Systems_Word_Problems/207571: The equation y= -1777x + 27,153 can be used to predict the number y of gun deaths in the United States x years after 2000, that is, x=0 corresponds to 2003, x=6 corresponds to 2006 and so on. Predict the number of gun deaths in 2006 and 2008. In what year will the number of gun deaths be 9383?
Gun deaths in 2006
Gun deths in 2008
Predicted number of gun deaths will be 9383 in the year
1 solutions
Answer 157078 by checkley77(12569) on 2009-08-20 18:11:06 (Show Source):
You can put this solution on YOUR website!y= -1777x + 27,153
y=-1,777*6+27,153
y=-10,662+27,153
y=16,491
------------------------
y=-1,777*8+27,153
y=14,216+27,153
y=12,937
---------------------------
9,383=-1,777x+27,153
1,777x=27,153-9,383
1,777x=17,770
x=17,770/1,777
x=10 or the year 2010
Gun deaths in 2006=16,491
Gun deths in 2008=12,937
Predicted number of gun deaths will be 9383 in the year=2010
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Travel_Word_Problems/207646: Maria drove at a steady speed for 5 hrs. on the turnpike. she then slowed her traveling speed by 15 miles per hour for traveling on secondary roads. the entire trip took 7 hours and covered 369 miles. what was her speed on the turnpike? 1 solutions
Answer 157073 by checkley77(12569) on 2009-08-20 17:59:55 (Show Source):
You can put this solution on YOUR website!d=rt
369=5x+(7-5)*(x-15)
369=5x+2(x-15)
369=5x+2x-30
369+30=7x
399=7x
x=399/7
x=57 mph. for the first 5 hrs.
57-15=42 mph for the last 2 hrs.
Proof:
369=5*57+2*42
369=285+84
369
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Geometry_Word_Problems/207656: Can you answer this: The length of a side of a rectangle is 4 inches more than the width. If the perimeter is 62 inches, what are the dimensions.
-Thanks 1 solutions
Answer 157056 by checkley77(12569) on 2009-08-20 17:33:40 (Show Source):
You can put this solution on YOUR website!2L+2W=PERIMETER
L=W+4
2(W+4)+2W=62
2W+8+2W=62
4W=62-8
4W=54
W=54/4
W=13.5 in. IS THE WIDTH.
L=13.5+4=17.5 in. IS THE LENGTH.
PROOF:
2*17.5+2*13.5=62
35+27=62
62=62
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Rectangles/207657: Find the length of a diagonal of a rectangle with l = 72 feet and w = 30 feet 1 solutions
Answer 157052 by checkley77(12569) on 2009-08-20 17:26:10 (Show Source):
You can put this solution on YOUR website!What you now have is a right triangle with sides of 72 & 30 ft.
Looking for the hypotenuse.
a^2+b^2=c^2
72^2+30^2=c^2
5,184+900=c62
c^2=6,084
c=sqrt6,084
c=78 ft. ans. for the diagonal(hypotenuse).
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Graphs/207610: A line passes through the points P(4,0) and Q(6,-4).
a) Calculate the slope of the line.
b) Write the equation of the line in slope-intercept form.
1 solutions
Answer 156994 by checkley77(12569) on 2009-08-20 10:01:53 (Show Source):
You can put this solution on YOUR website!Y=mX+b
m=slope=(y2-y1)/(x2-x1)=(-4-0)/6-4)=-4/2=-2 is the slope.
a)=-2
0=-2*4+b
0=-8+b
b=8 is the y intercept.
b) Y=-2X+8
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, -2x +8).
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