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Label each system as consistent or inconsistent.
Thank you.
w + 8s = - 42
-9w - s = -48 1 solutions
Answer 196243 by checkley77(12569) on 2010-02-08 21:04:49 (Show Source):
You can put this solution on YOUR website!w + 8s = - 42 multiply by 9 & add.
-9w - s = -48
9w+72s=-378
--------------------
71s=-426
s=-426/71
s=-6 ans.
w+8*-6=-42
w-48=-42
w=-42+48
w=6 ans.
Proof:
-9*6-(-6)=-48
-54+6=-48
-48=-48
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Systems-of-equations/267302: Find the equation of the line containing the point (2,-5) and perpendicular to the line y=5/2x-4. 1 solutions
Answer 196236 by checkley77(12569) on 2010-02-08 20:44:47 (Show Source):
You can put this solution on YOUR website!(2,-5) and perpendicular to the line
y=5x/2-4 (red line)
Slope=5/2.
The perpendicular line will have a slope=-2/5.
-5=2*-2/5+b
-5=-4/5+b
b=-5+4/5
b=-25/5-4/5
b=-29/5 ans. for the Y intercept.
y=-2x/5-29/5 (green line)
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions 5x/2 -4 and -2x/5 -29/5).
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Linear-equations/267326: Find an equation for the line with given properties parallel to the line 2x-y=7 containing the point 0,0 1 solutions
Answer 196233 by checkley77(12569) on 2010-02-08 20:35:00 (Show Source):
You can put this solution on YOUR website!Parallel to 2x-y=7 through 0,0
2x-y=7
-y=-2x+7
y=-2x/-1+7/-1
y=2x-7 (red line)
A parallel line will have a slope=2.
y=2x+0 (green line)
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions 2x +7 and y = 2x).
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Mixture_Word_Problems/267345: please solve
a solution containing 30% juice is mixed with a solution containing 10% juice to make 100 gallons of solution that makes 12% juice.How much of the 30% solution was used? 1 solutions
Answer 196226 by checkley77(12569) on 2010-02-08 20:17:28 (Show Source):
You can put this solution on YOUR website!.30x+.10(100-x)=.12*100
.30x+10-.10x=12
.20x=12-10
.20x=2
x=2/.2
x=10 gallons of 30% solution is used.
100-10=90 gallons 0f 10% is used.
Proof:
.30*10+.10*90=.12*100
3+9=12
12=12
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Probability-and-statistics/267191: A miniature golf course offers a free game to golfers who make a hole-in-one on the last hole. Last week, 44 out of 288 golfers made a hole-in-one on the last hole. Find the experimental probability that a golfer makes a hole-in-one on the last hole.
Please round your answer to two decimal places. 1 solutions
Answer 196172 by checkley77(12569) on 2010-02-08 16:38:15 (Show Source):
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Linear-equations/267192: The Directions Say "Solve The Following System Of Equations."
And The Problem Is.....
4x+6y=9
10x-18y=-5 1 solutions
Answer 196171 by checkley77(12569) on 2010-02-08 16:36:15 (Show Source):
You can put this solution on YOUR website!4x+6y=9 multiply by 3 & add.
10x-18y=-5
12x+18y=27
----------------
22x=22
x=22/22
x=1 ans.
4*1+6y=9
4+6y=9
6y=9-4
6y=5
y=5/6 ans.
Proof:
10*1-18*5/6=-5
10-90/6=-5
10-15=-5
-5=-5
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Rectangles/267194: The length of a rectangle is 2 inches more than its width.The area of the rectangle is 15 square inches. What are the length and width of the rectangle? 1 solutions
Answer 196170 by checkley77(12569) on 2010-02-08 16:32:32 (Show Source):
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Permutations/266394: How many ways can 6 students desks be arranged in a row? explain 1 solutions
Answer 195722 by checkley77(12569) on 2010-02-06 19:01:56 (Show Source):
You can put this solution on YOUR website!6!=6*5*4*3*2*1=720 different ways these desks can be arrangesd in a row.
Any one of the 6 desks can be first.
Any one of the remaining 5 desks can be second.
Any one of the remaining 4 desks can be third.
Any one of the remaining 3 desks can be fourth.
Any one of the remaining 2 desks can be fifth
The one desk left takes the last place in the row.
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test/266414: two trains start from the same station and run in opposite directions. one runs at a uniform rate of 30km an hour and the other runs at 35km an hour. in how many hours will they be 195km apart? 1 solutions
Answer 195716 by checkley77(12569) on 2010-02-06 18:49:05 (Show Source):
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Mixture_Word_Problems/266418: A chemist obtain 18 grams of 10% saline solution from a mixture of 5% saline solution and a 15% saline solution. How much of the 15% saline solution is used in the mixture? 1 solutions
Answer 195714 by checkley77(12569) on 2010-02-06 18:46:07 (Show Source):
You can put this solution on YOUR website!.15X+.05(18-X)=.10*18
.15X+.9-.05X=1.8
.10X=1.8-.9
.10X=.9
X=.9/.10
X=9 GRAMS OF 15% SOLTION IS USED.
PROOF:
.15*9+.05(18-9)=.10*18
1.35+.05*9=1.8
1.35+.45=1.8
1.8=1.8
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Permutations/266419: Kurt, yoel, Jason, Elana and Sara are studying together for a Finite Test. They decide to get a snack. Each is allowed to take one snack item. In how many different ways can the snacks be distributed if there are 6 apples, 5 oranges, 4 pieces of cherry, and 3 blueberry muffins? 1 solutions
Answer 195713 by checkley77(12569) on 2010-02-06 18:40:47 (Show Source):
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Linear-systems/266425: please help me solve this problem
category:coins and money
1.Alice is counting a cash register at the end of the night.she has $1015 in $5 bills and $10 bills.if she has 138 bills all together,how many of each type does she has?
please help me right away. 1 solutions
Answer 195710 by checkley77(12569) on 2010-02-06 18:31:28 (Show Source):
You can put this solution on YOUR website!f+t=138 or f=138-t
5(138-t)+10t=1015
690-5t+10t=1015
5t=1015-690
5t=325
t=325/5
t=65 ten dollar bills.
f=138-65=73 ten dollar bills.
Proof:
5*73+10*65=1015
365+650=1015
1015=1015
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Graphs/266360: I= prt solve for p; solve for r; solve for t
F= 9/5 C + 32 solve for C
A= 1/2 Bh solve for B; solve for h
A= LW solve for L; solve for W
P= 2L + 2W solve for L; solve for W
C= 2(3.14))r solve for r
G= 3.5M/P solve for M; solve for P
D= M/V solve for M; solve for V 1 solutions
Answer 195708 by checkley77(12569) on 2010-02-06 18:19:36 (Show Source):
You can put this solution on YOUR website!I= prt solve for p; solve for r; solve for t
p=I/rt ans
r=I/pt ans.
t=I/pr ans.
F= 9C/5 + 32 solve for C
9C/5=F-32
9C=5(F-32)
9C=5F-160
C=(5F-`60)/9 ans.
A= 1/2 Bh solve for B; solve for h
a=Bh/2
Bh=2a
B=2a/h ans.
h=2a/B ans.
A= LW solve for L; solve for W
L=A/W ANS.
W=A/L ANS
P= 2L + 2W solve for L; solve for W
2L=P-2W
L=(P-2W)/2 ANS.
2W=P-2L
W=(P-2L)/W
C= 2(3.14)r solve for r
r=c/(2*3.14) ans.
G= 3.5M/P solve for M; solve for P
3.5M=GP
M=GP/3.5 ANS.
GP=3.5M
P=3.5M/G ANS.
D= M/V solve for M; solve for V
M=DV ANS.
DV=M
V=M/D ANS.
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Systems-of-equations/266368: Trains A and B are traveling in the same direction on parallel tracks. Train A is traveling at 100 miles per hour and Train B is traveling at 110 miles per hour. Train A passes a station at 10:15 A.M. If train B passes the same station at 10:27 A.M., at what time will train B catch up to train A?
I know the equation is
100t = 110(t - something)
I know there is 12 minutes difference, but I do not know how to put 12 minutes in a decimal form.
Could someone please help me with this, I would appreciate it very much. 1 solutions
Answer 195706 by checkley77(12569) on 2010-02-06 18:06:17 (Show Source):
You can put this solution on YOUR website!100t=110(t-12/60)
100t=110(t-1/5)
100t=110t-22
100t-110t=-22
-10t=-22
t=-22/-10
t=2.2 hours after train A leaves the station they will meet.
OR: 10:15+2:12=12.27 is the time of the meet.
Proof:
100*2.2=110(2.2-1/5)
220=242-22
220=220
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Rectangles/266369: the length of a rectangular field is 7 meters more than twice it width. the perimeter is 140 meters, find the dimension of the field 1 solutions
Answer 195705 by checkley77(12569) on 2010-02-06 17:58:46 (Show Source):
You can put this solution on YOUR website!L=2W+7
2L+2W=140
2(2W+7)+2W=140
4W+14+2W=140
6W=140-14
6W=126
W=126/6
W=21 ANS. FOR THE WIDTH.
L=2*21+7=42+7=49 ANS. FOR THE LENGTH.
PROOF:
2*49+2*21=140
98+42=140
140=140
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