SOLUTION: Please help me solve this system of equations:
Directions: Solve using elimination and using the matrix method
x+y+z=6
2x-3y+5z=-11
x+3y-4z=19
Work I have done so far:
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-> SOLUTION: Please help me solve this system of equations:
Directions: Solve using elimination and using the matrix method
x+y+z=6
2x-3y+5z=-11
x+3y-4z=19
Work I have done so far:
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Question 660956: Please help me solve this system of equations:
Directions: Solve using elimination and using the matrix method
x+y+z=6
2x-3y+5z=-11
x+3y-4z=19
Work I have done so far:
x+y+z=6
-x-3y+4z=-19 This equals -2y+5z=-13 equation #1
-2x-6y+8z=-38
2x-3y+5z=-11 This equals -9y+13z=-49 equation #2
Multiply equation #1 by -9 and multiply equation #2 by 2
18y+45z=117
-18y-26z=-98 z= -19/71
At this point I got stuck because my teacher said that all answers would be nice even numbers. When I solved the equations using the matrix method (I know how to do this part) I got (3,4,-1) which I checked and is the correct answer.
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Please help me solve this system of equations:
Directions: Solve using elimination and using the matrix method
x+y+z=6
2x-3y+5z=-11
x+3y-4z=19
Work I have done so far:
x+y+z=6
-x-3y+4z=-19 This equals -2y+5z=-13 equation #1
-2x-6y+8z=-38
2x-3y+5z=-11 This equals -9y+13z=-49 equation #2
Multiply equation #1 by -9 and multiply equation #2 by 2
18y+45z=117
-18y-26z=-98 z= -19/71
At this point I got stuck because my teacher said that all answers would be nice even numbers. When I solved the equations using the matrix method (I know how to do this part) I got (3,4,-1) which I checked and is the correct answer.
It would seem as though you multiplied - 9y + 13z = - 49 by 2, which results in: - 18y + 26z = - 98, NOT - 18y - 26z = - 98. This is where you went wrong. Look into this and you should be fine. My elimination-solution is below.
