4 similarity and pythagorean theorem

Answer:
B) 26
Step-by-step explanation:
The smaller triangle drawn using bigger triangle are similar so we can use the similarity ratio to find the missing side:
10/20 = 12/24 simplify expressions
1/2 = 1/2 is the similarity ratio so if we let x represent the missing side then
13/x = 1/2 cross multiply expressions
x = 26