Answer:
32
Step-by-step explanation:
Side AD = 4
9-5=4
Side DC = 13
a^2+b^2=c^2
5^2+12^2=c^2
25+144=c^2
169=c^2
13=c
Side AC = 15
9^2+12^2=c^2
81+144=c^2
225=c^2
15=c