Answer: XY = 8
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Step-by-step explanation:
Highlight XY in the sequence XYZ. We've highlighted the first two letters.
This means that we'll need to highlight the first two letters of MNL to get MN.
XY pairs with its corresponding part MN.
Due to the congruent triangles, we know that XY = MN.
The diagram shows MN = 8. Due to substitution or the transitive property (they're similar ideas) we know that XY = 8 as well.
As you can see, the order of the letters is important so we can properly align the letters.