http://img74.imageshack.us/img74/337...glezju8.th.png

Given: AB=20, BC=7, CA=15, triangle DAB is ~ to triangle DCA.

FIND DC.

Yea, show all work, no fancy stuff, you probably can do it with a few proportions then substitution, you will need to find y first to find x...

once again, show all work.

thanks!