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There are no tick marks to indicate which angles are congruent between these two similar triangles. I will assume both triangles have the same orientation and that the corresponding parts are follow that orientation.

We use Property Of Similar Triangles to set up our proportion:

4/6 = 5/m

and 4 / 6 = n / 4.5

Solve for m in 4/6 = 5/m, m = 5*6/4 = 15/2 = 7.5

m=7.5

n=3

since n = 4.5 * (4/6) = 3

Answer Choice A.) n = 3 and m = 7.5

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