Answer:
5 feet
Explanation:
You are not looking for an angle....you need a side length
for a right triangle , yo can use the Pythagorean theorem
a^2 + b^2 = c^2 where a and b are LEGS and c is the hypotenuse
12^2 + ?^2 = 13^2
?^2 = 169 - 144
?^2 = 25
? = 5 feet