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PLEASE HELP!!!!!!!!!

PLEASE HELP!!!!!!!!!-example-1

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Part A.

The sum of the first two equations is (2x +3y -z) +(x -3y +2z) = (5) +(-6), or 3x +z = -1.

Part B.

A good next-step in the process is to eliminate y from another equation, such as by adding the second equation to 3 times the third one. Doing that would give two equations in the two unknowns x and z, making a simpler system to solve.

... (x -3y +2z) +3(3x +y -4z) = (-6) +3(-8)

... 10x -10z = -30

Dividing this equation by 10 gives

... x - z = -3

Part C.

Adding the equation just found to the one of Part A gives ...

... (x -z) + (3x +z) = (-3) +(-1)

... 4x = -4

... x = -1

... z = x + 3 = 2

... y = -8 +4z -3x . . . . from the third original equation

... y = -8 +8 -3(-1) = 3

The solution is (x, y, z) = (-1, 3, 2).

Yes, it works when you test it.

... 2(-1) +3(3) -(2) = 5

... (-1) -3(3) +2(2) = -6

... 3(-1) +(3) -4(2) = -8

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