Answer:
XY = 18
Step-by-step explanation:
The figures are similar so the ratios of corresponding sides are equal, that is
[tex]\frac{XY}{BC}[/tex] = [tex]\frac{YZ}{CD}[/tex] , substitute values
[tex]\frac{XY}{12}[/tex] = [tex]\frac{15}{10}[/tex] ( cross- multiply )
10 XY = 180 ( divide both sides by 10 )
XY = 18