Hi,
1)Tickets for a concert sold for $11 and $8. If 600 tickets were sold for one evening and the the receipts are $5550, how many of each kind of tickets were sold?
Let x = number of $11 tickets
Let y = number of $8 tickets
x + y = 600 <-- total number of tickets
11x + 8y = 5550 <-- total cost of tickets
Multiply the top equation by -8. Then add equations together. "y" will drop out and then solve for x.
-8(x + y = 600)
11x + 8y = 5550
-8x - 8y = -4800
11x + 8y = 5550
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3x = 750
x = 250, so there are 250 $11 tickets
If x = 250, then 250 + y = 600
y = 350, so there are 350 $8 tickets
2)Solve by substitution--
x+2y=10
y=2x
Replace y in the first equation with 2x.
x + 2(2x) = 10
x + 4x = 10
5x = 10
x = 2
Find y by plugging in x = 2.
If y = 2x, then y = 2(2) so y = 4.
The answer is (2,4).
2)Solve by substitution--
2x+y=9
x-3y=22
Solve the 2nd equation for x.
x - 3y = 22
x = 3y + 22
Substitute this expression into the first equation in place of x.
2x + y = 9
2(3y + 22) + y = 9
6y + 44 + y = 9
7y + 44 = 9
7y = -35
y = -5
Substitute -5 for y and solve for x.
2x + y = 9
2x - 5 = 9
2x = 14
x = 7
So the answer is (7,-5).
I hope those help you!! :-)
2007-07-30 16:24:21
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answer #1
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answered by Pi R Squared 7
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1)Tickets for a concert sold for $11 and $8. If 600 tickets were sold for one evening and the the receipts are $5550, how many of each kind of tickets were sold?
11x + 8y = 5550
x + y = 600
x = 600 - y
11(600 - y) + 8y = 5550
6600 - 11y + 8y = 5550
-3y = -1050
y = 350
x + y = 600
x = 600 - y
x = 600 - (350)
x = 250
350 tickets were $8
250 tickets were $11
2)
x+2y=10
y=2x
x + 2(2x) = 10
x + 4x = 10
5x = 10
x = 2
y = 2x
y = 2(2)
y = 4
and
2x+y=9
x-3y=22
x - 3y = 22
x = 22 + y
2x + y = 9
2(22 + y) + y =9
44 + 2y + y = 9
3y = -35
y = -35/3
x - 3y = 22
x = 22 + 3y
x = 22 + 3(-35/3)
x = 22 - 35
x = -13
2007-07-30 23:35:10
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answer #2
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answered by peachi517 2
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For the tickets:
First let X = the number of $11 tickets
Then 600-X would be the number of $8 tickets
We know the total value was 5550$; so,
11X + 8 x [600-X] = 5550
11X + 4800 - 8X = 5550
11X -8X = 5550 - 4800
3X = 750
X = 250 so 250 11$ tickets and [600-250] 8$ tickets.
Check your answer: [250 x 11] + [350 x 8] = 5550
X + 2Y = 10; Y = 2X (substitute 2X for Y in 1st equation)
X +2(2X) = 10 >> X + 4X = 10 >>5X = 10 >>X =2
2007-07-30 23:22:36
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answer #3
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answered by Flying Dragon 7
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1)
11x + 8y = 5550
x + y = 600
y = 600 - x
substitute:
11x + 8(600 - x) = 5550
11x + 4800 - 8x = 5550
x = (5550 - 4800)/3
x = 250
y = 600 - 250 = 350
2)
x + 2y = 10
y = 2x
x + 2(2x) = 10
x = 10/5
x = 2
y = 2(2) = 4
3)
2x + y = 9
x - 3y = 22
x = 22 + 3y
2(22 + 3y) + y = 9
44 + 6y + y = 9
44 + 7y = 9
y = -5
2x - 5 = 9
x = 7
2007-07-30 23:43:41
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answer #4
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answered by ferdie 2
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1) let number of 11 bucks tix to x and let number of 8 bucks tix to be y.
Total tickets sold is 600. So x+y=600. This is ur first equation.
Then total receipts is 5500. So 11x +8y=5500. This is ur second equation.
x +y=600
Therefore, x=600-y
Subtitute ur x into the second equation which you derived earlier one, and you'll have the answer.
2) Since y=2x, so
x+2y=10
x+2(2x)=10
x+4x=10
5x=10
x=2
x-3y=22
so, x=22+3y
Sub x=22+3y into 2x+y=9
You'll have 2(22+3y)+y=9
which is equal to 44+6y+y=9
7y=9-44
7y= -35
therefore, y=5
2007-07-30 23:22:47
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answer #5
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answered by girl 2
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1) set it up like this-------------> 11x + 8y = $5550
You do it yourself.
2) 3x = 10
and
7y = -35
You should do these yourself...
2007-07-30 23:18:48
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answer #6
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answered by Anonymous
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