SOLUTION: solve the system using any method. 5x-3y+7z=25 x+2y+z=9 3y-z=3

Algebra ->  Matrices-and-determiminant -> SOLUTION: solve the system using any method. 5x-3y+7z=25 x+2y+z=9 3y-z=3      Log On


   

Question 676152: solve the system using any method.
5x-3y+7z=25
x+2y+z=9
3y-z=3
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Hint:

3y-z=3

z = 3y - 3

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x+2y+z=9

x+2y+3y-3=9

x+5y = 12

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5x-3y+7z=25

5x-3y+7(3y-3)=25

5x-3y+21y-21=25

5x+18y=46

So we then get the system

x+5y = 12
5x+18y=46

Solve this for x and y. Then use y to find z.