Answer:
The answer to your question is 12 m
Step-by-step explanation:
Data
height = 5 m
the distance the squirrel flyed= 13 m
the distance from the three to the acorn = ?
Process
1.- To solve this problem use the Pythagorean theorem
       c² = a² + b²
c = 13
a = 5
b = x
2.- Solve for b
           b² = c² - a²
3.- Substitution
           b² = 13² - 5²
4.- Simplification
           b² = 169 - 25
           b² = 144
5.- Result
           b = 12 m
6.- The distance from the three to the acorn is 12 m