SOLUTION: i am working on solving problems wit h3 variables. it has been over an hour and can't get a correct answer. it seems easy, but i am having no luck.
if I could see the work to arri
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-> SOLUTION: i am working on solving problems wit h3 variables. it has been over an hour and can't get a correct answer. it seems easy, but i am having no luck.
if I could see the work to arri
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Question 234909: i am working on solving problems wit h3 variables. it has been over an hour and can't get a correct answer. it seems easy, but i am having no luck.
if I could see the work to arrive the right answers that would be great. i have the answers in the back of my book.
2x-3y+z=5
x+3y+8z=22
3x-y+2z=12 Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! 2x-3y+z=5
x+3y+8z=22
3x-y+2z=12
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Let the 2nd equation become the 1st:
x+3y+8z=22
2x-3y+z=5
3x-y+2z=12
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Subtract 2 times the 1st from the 2nd;
Subtract 3 times the 1st from the 3rd.
x+3y+8z=22
0-9y-15z=-39
0-10y-22z=-54
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Subtract 3rd from 2nd to get:
x+3y+8z=22
0+y+7z=15
0-10y-22z=-54
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Add 10 times 2nd to 3rd to get:
x+3y+8z=22
0+y+7z=15
0+0+48z=96
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Divide thru 3rd by 48 to get z = 2
x+3y+8z=22
0+y+7z=15
0+0+z=2
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Substitute z=2 into the 2nd and into the 1st lines:
x+3y+16=22
0+y+14=15
0+0+z=2
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Solve the 2nd for y: y = 1
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Substitute that into the 1st to get:
x + 3*1+16=22
0 + y + 0 = 1
0 + 0 + z = 2
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solve the 1st for x: x = 3
--------------------------------
x = 3
y = 1
x = 2
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Cheers,
Stan H.
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