Question 201237: The sum of three numbers is 15, the sum of twice the first number,4 times the second number and five times the the third number is 49. the difference between 4 times the first number and the second number is 23. find the three numbers in there order???
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! The sum of three numbers is 15, the sum of twice the first number,4 times the second number and five times the the third number is 49. the difference between 4 times the first number and the second number is 23. find the three numbers
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x + y + z = 15
2x+4y +5z = 49
4x-y = 23
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Add Eqn 1 and 3
5x + z = 38 Eqn A
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Multiply eqn 3 by 4 and add to eqn 2.
2x+4y +5z = 49
16x-4y = 92
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18x + 5z = 141 Eqn B
Multiply Eqn A by -5 and add it to Eqn B
18x + 5z = 141 Eqn B
-25x -5z = -190
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-7x = -49
x = 7 xxxxxxxxxxxxxxxx
Sub for x into Eqn A
5*7 + z = 38
z = 3 zzzzzzzzzzzzzzzzz
Sub for x and z into eqn 1
x + y + z = 15
7 + y + 3 = 15
y = 5 yyyyyyyyyyyyyyyy
7, 5, 3 are the numbers.
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