in a right triangle ABC, if ab is 14 and bc is 12 wut is bd?

Question

there is a pic of a large trangle abc and in it is a line drawn down angle c making it line cd. angle acd then becomes a right trangle as well.

i tried working = proportions and pyth thm but i don't seem to be getting the right answer.

You have similar triangles.

if they are similar triangles how would i work out the proportions since only two values are given.