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checkley77 answered: 12560 problems
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How do i know if a line is or segments are parallel? the assignment wants me to answer with a theorem or postulate. Can some one please explain to me how i will figure that out? 1 solutions
Answer 170062 by checkley77(12569) on 2009-10-20 19:10:15 (Show Source):
You can put this solution on YOUR website!LINES ARE PARALLEL IF THEIR SLOPES ARE EQUAL.
EXAMPLE:
Y=3X/5+3 (RED LINE)
Y=3X/5-4 (GREEN LINE)
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions 3x/5 +3 and 3x/5 -4).
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Volume/229266: The volumes of two cubes differ by 259 cu meters. If the edges of one cube are each 4 meters greater than the edges of the other, what is the sum of the lengths of one edge of each cube? 1 solutions
Answer 170058 by checkley77(12569) on 2009-10-20 19:02:56 (Show Source):
You can put this solution on YOUR website!X^2-Y^2=259
X=Y+4
(Y+4)^2-Y^2=259
Y^2+8Y+16-Y^2=259
8Y=259-16
8Y=243
Y=243/8
Y=30.375 ANS FOR THE SMALLER SQUARE SIDES.
X=30.375+4
X=34.375 ANS FOR THE LARGER SQUARE SIDES.
PROOF:
34.375^2-30.375^2=259
11.81.64-922.64=259
259=259
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Rectangles/229273: An area of 52 square feet is to be enclosed by two squares whose sides are in the ratio of 2:3. Find the sides of the two squares. 1 solutions
Answer 170053 by checkley77(12569) on 2009-10-20 18:47:37 (Show Source):
You can put this solution on YOUR website!(2X)^2+(3X)^2=52
4X^2+9X^2=52
13X^2=52
X^2=52/13
X^2=4
X=2 ANS FOR THE SIDES OF THE SMALLER SQUARE.
PROOF:
(2*2)^2+(3*2)^2=52
4^2+6^2=52
16+35=52
52=52
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Travel_Word_Problems/229278: Twp cyclists start biking from a trails start 3 hours apart. The second cyclist travels at 10 miles per hour and starts 3 hours after the first cyclist who is traveling at 6 miles per hour. How much time will pass before the second cyclist catches up with the first from the time the second cyclist started biking? 1 solutions
Answer 170051 by checkley77(12569) on 2009-10-20 18:38:45 (Show Source):
You can put this solution on YOUR website!D=RT
D=6T
D=10(T-3)
6T=10(T-3)
6T=10T-30
6T-10T=-30
-4T=-30
T=-30/-4
T=7.5 HOURS THEY WILL MEET.
PROOF:
6*7.5=10(7.5-3)
45=10*4.5
45=45
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Travel_Word_Problems/229287: Stan can drive from Atlas to Billings at a constant rate in four hours. If he increases his rate by 15 miles per hour, he could complete the trip in three hours. Find the number of miles between Atlas and Billings. 1 solutions
Answer 170048 by checkley77(12569) on 2009-10-20 18:34:17 (Show Source):
You can put this solution on YOUR website!D=RT
D=R*4
D=(R+15)3
4R=3R+45
4R-3R=45
R=45 MPH IS THE RATE FOR THE 4 HOUR TRIP.
D=45*4=180 MILES IS THE DISTANCE BETWEEN ATLAS & BILLINGS.
D=(45+15)3
D=60*3
D=180 DITTO.
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Travel_Word_Problems/229288: Jack starts at the summit of Mt. Mickinley (elevation 20,320) and travels down the mountain at a rate of 4 feet per second. Jill starts at the bottom at the same time and travels up the mountain at a rate of 1 foot per second. At what elevation, in feet, will they meet? 1 solutions
Answer 170047 by checkley77(12569) on 2009-10-20 18:28:51 (Show Source):
You can put this solution on YOUR website!4x+1x=20,320
5x=20,320
x=20,320/5
x=4,064 sec. after they start they will meet.
1*4,064=4,064 feet is the meeting altitude.
Proof:
4*4064=16,256 feet below the peak.
16,256+4,064=20,320
20,320=20,320
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absolute-value/229289: -|3n-5| is greater than or equal to 7n-15
I don't understand how to show the absolute value when it is negative.
Please show good, concise steps. 1 solutions
Answer 170043 by checkley77(12569) on 2009-10-20 18:22:34 (Show Source):
You can put this solution on YOUR website!-|3n-5|>=7n-15
-3n+5>=7n-15
-3n-7n>=-15-5
-10n>=-20
n<=-20/-10 [Note: when dividing by a negative value the > sign changes to a < sign]
n<=2 ans.
Proof:
Let n=1.9
-[3*1.9-5]>=7*1.9-15
-[5.7-5]>=13.3-15
-[.7]>=-1.7
-.7>=-1.7
--------------------------
-[3n-5]>=-(7n-15)
-3n+5>=-7n+15
-3n+7n>=15-5
4n>=10
n>=10/4
n>=2.5 ans.
Proof:
Let x=2.6
-[3*2.6-5]>=-(7*2.6-15)
-(7.8-5]>=-(18.2-15)
-(2.8)>=-3.8
-2.8>=-3.8
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Inequalities/229290: Expenses. The sophomore class is planning a picnic. The cost of a permit to use a city park is $250. To pay for the permit, there is a fee of $.75 for each sophomore and $1.25 for each guest who is not a sophomore. Two hundred sophomores plan to attend. Write and solve an inequality to find how many guests must attend for the sophomores to pay for the permit. 1 solutions
Answer 170038 by checkley77(12569) on 2009-10-20 18:08:07 (Show Source):
You can put this solution on YOUR website!200*.75+1.25x>250
150+1.25x>250
1.25x>250-150
1.25x>100
x>100/1.25
x>80 minimum number of non sophomores are required to raise the $250 fee.
Proof:
200*.75+1.25*80>250
150+100=250
250=250
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Linear-equations/229194: Find the equation of a line parallel to 4y=2x+6 through the point (-4,5) 1 solutions
Answer 170031 by checkley77(12569) on 2009-10-20 17:53:45 (Show Source):
You can put this solution on YOUR website!4y=2x+6 through the point (-4,5)
y=2x/4+6/4
y=x/2+3/2 this line has a slope=1/2. (red line)
Thus a parallel line will also have a slope=1/2.
Y=mX+b
5=1/2*-4+b
5=-2+b
b=5+2
b=7
Y=X/2+7 the equation for the parralel line through (-4,5). (green line).
 (graph 300x300 pixels, x from -10 to 10, y from -10 to 10, of TWO functions x/2 +3/2 and x/2 +7).
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Money_Word_Problems/229217: You invested $8000, part at 5% and part at 6%. The total interest earned in one year what $468. How much was invested at each rate? 1 solutions
Answer 170023 by checkley77(12569) on 2009-10-20 17:29:23 (Show Source):
You can put this solution on YOUR website!.06x+.05(8,000-x)=468
.06x+400-.05x=468
.01x=468-400
.01x=68
x=68/.01
x=6,800 amount invested @ 6%.
8,000-6,800=1,200 amount invested @ 5%.
Proof:
.06*6,800+.05*1,200=468
408+60=468
468=468
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Rectangles/229229: The length of a rectangle is 8 in. more than its width. the perimeter of the rectangle is 24 in. what anr the width and length of the rectangle? 1 solutions
Answer 170005 by checkley77(12569) on 2009-10-20 17:00:36 (Show Source):
You can put this solution on YOUR website!L=W+8
2L+2W=24
2(W+8)+2W=24
2W+16+2W=24
4W=24-16
4W=8
W=8/4
W=2 ANS. FOR THE WIDTH.
L=2+8=10 ANS. FOR THE LENGTH.
PROOF:
2*10+2*2=24
20+4=24
24=24
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Numbers_Word_Problems/229234: Caleb was studying the menu at his favorite restaurant. He has these choices.
1st course-soup or salad
2nd course-chicken, beef or fish
3rd course-pie or cake
Show all combinations at his three course meal 1 solutions
Answer 169999 by checkley77(12569) on 2009-10-20 16:51:33 (Show Source):
You can put this solution on YOUR website!1st course-soup or salad
2nd course-chicken, beef or fish
3rd course-pie or cake
-------------------------------
soup,chicken,pie
soup,chicken,cake
soup,beef,pie
soup,beef,cake
soup,fish,pie
soup,fish,cake
salad,chicken,pie
salad,chicken,cake
salad,beef,pie
salad,beef,cake
salad,fish,pie
salad,fish,cake
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Graphs/229236: SOLVE BY GRAPHING.
3X+2Y=8
6X+4Y=16 1 solutions
Answer 169997 by checkley77(12569) on 2009-10-20 16:46:00 (Show Source):
You can put this solution on YOUR website!3X+2Y=8
2y=-3x+8
y=-3x/2+8/2
y=-3x/2+4 (red line)
6X+4Y=16
4y=-6x+16
y=-6x/4+16/4
y=-3x/2+4 (green line)
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions -3x/2 +4 and -3x/2 +4).
These 2 lines are identical.
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Age_Word_Problems/228989: In 1985,B is 13. A is 43. In what year will B be 2/5 of A's age? 1 solutions
Answer 169901 by checkley77(12569) on 2009-10-19 22:52:53 (Show Source):
You can put this solution on YOUR website!(13+X)=2/5(43+X)
13+X=86/5+2X/5
X-2X/5=86/5-13
.6X=(86-13*5)/5
.6X=(86-65)/5
.6X=21/5
X=(21/5)/.6
X=21/5*1/.6
X=21/3
X=7 YEARS AFTER 1985 OR 1992 B WILL BE 2/5 THE AGE OF A.
PROOF:
13+7=2/5(43+7)
20=2/5*50
20=100/5
20=20
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Equations/228991: 6(x)-7=2(x)+29
54-7=18+29
47=47
I had help on this equation a little while ago. My teacher had given me the answer and done the work without knowing it. I know that answer is x=9 But on the test I will be completely lost! Please help me.
Amber A 1 solutions
Answer 169899 by checkley77(12569) on 2009-10-19 22:40:42 (Show Source):
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Points-lines-and-rays/229017: Respected sir,
plz help me to solve perimeter problem.
1] The area of a square garden is A square feet and the perimeter is P feet.If A=2P+9,what is the perimeter of the garden,in feet?
waiting for yur reply.
thank u.
1 solutions
Answer 169892 by checkley77(12569) on 2009-10-19 22:33:11 (Show Source):
You can put this solution on YOUR website!A=2P+9
X^2=A
P=4X
REPLACE A WITH X^2 & REPLACE P WITH 4X & SOLVE FOR X THE SIDE OF THE SQUARE.
X^2=2*4X+9
X^2=8X+9
X^2-8X-9=0
(X-9)(X+1)=0
X-9=0
X=9 ANS FOR THE SIDE OF THE SQUARE.
PROOF:
9^2=2*4*9+9
81=72+9
81=81
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Linear-equations/229018: what is the solution for the following system of linear equations?
X+6Y=-4
3X-4Y=10 1 solutions
Answer 169889 by checkley77(12569) on 2009-10-19 22:27:27 (Show Source):
You can put this solution on YOUR website!X+6Y=-4 MULTIPLY THIS EQUATION BY -3 7 ADD,
3X-4Y=10
-3X-18Y=12
-----------------
-22Y=22
Y=22/-22
Y=-1 ANS.
X+6*-1=-4
X-6=-4
X=-4+6
X=2 ANS.
PROOF:
3*2-4*-1=10
6+4=10
10=10
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THE ANSWER IS (2,-1) NORMALLY THESE TERMS ARE PRESENTED AS (X,Y)
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Square-cubic-other-roots/229024: OK here is my last one another square root question and it is a fraction also.
sqrt(?) _77_
sqrt(?) 33
They are both to the square root and it is 77 over 33 in a fraction. Am I close at all when I say 3.66? Probably not right?? Help please.
1 solutions
Answer 169887 by checkley77(12569) on 2009-10-19 22:22:28 (Show Source):
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