If N is parallel to M find the value of x and the value of z. A. x=9, z=2
B. x=9, z=1.5
C. x=18, z=1.5
D. x=8, z=5
D is incorrect

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.

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