Answer: No solutions
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Step-by-step explanation:
Subtract the second equation from the first one
Let's call that result equation 4.
Now focus on equation 3 and equation 4
equation 3 is -x+7y-6z = 2
equation 4 is -x+7y-6z = 5
Note how the left hand sides are identical, but the right hand sides are different. This means that we have an inconsistent system with no solutions. No matter what numbers we pick for x,y,z, there is no way to make all three given original equations to be true.