A is the answer, the proportion RS/VU=2, the proportion of ST/UT=2, an angle S is equal to angle U, both 90 degrees. RS/VU, side, angle S = to angle U, angle and ST/UT, side.
I did not even understand that equation

Divide both the numerator and denominator by 9 to get;

Convert the improper fraction to a mixed number;
(16y6)3 - (10z2)3 I think is the right answer