SOLUTION: 3x+4y+5z=18,2x-y+8z=13,5x-2y+7z=20

Algebra ->  Matrices-and-determiminant -> SOLUTION: 3x+4y+5z=18,2x-y+8z=13,5x-2y+7z=20      Log On


   

Question 1126612: 3x+4y+5z=18,2x-y+8z=13,5x-2y+7z=20
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Not a complete solution - just a possible way to use few steps -

system%283x%2B4y%2B5z=18%2C2x-y%2B8z=13%2C5x-2y%2B7z=20%29


4*E2+E1 to eliminate y
and
-2E2+E3 to eliminate y

system%284x%2B9z=90%2Cx%2B9z=-6%29


E1-E2 to eliminate z
3x=96
highlight%28x=32%29-------one of the variables now found.

Use either equation from previous system to get y and z.

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system%28y=155%2F9%2Cz=-38%2F9%29