The given angles are
M = 64
N = 48
where P is unknown. While we don't know P at first, we can solve for it. Recall that for any triangle, the three angles always add to 180 degrees
M+N+P = 180
64+48+P = 180
112+P = 180
112+P-112 = 180-112
P = 68
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So in summary so far
M = 64
N = 48
P = 68
The shortest side is opposite the smallest angle. The side MP is opposite the smallest angle N = 48
The longest side is going to be opposite the largest angle. In this case, side MN is opposite the largest angle P = 68
The medium side is opposite the medium angle. So NP is the medium side length
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Final Answers:
Shortest Side = MP
Medium Side = NP
Longest Side = MN
See the attached image for a visual summary
The ascending order would be: MP, NP, MN
Note: Something like MP is the same as PM. The order of endpoints for any given individual segment doesn't matter