I need help on this problem

c= 15 mi

Step-by-step explanation:

Pythagorean theorem.  a^+b^=c^

Square root of that

answer 15

15

Step-by-step explanation:

Since this is a right triangle, we can use the Pythagorean theorem

a^2 + b^2 = c^2  where a and b are the legs and c is the hypotenuse

9^2 + 12 ^2 = c^2

81+144= c^2

225 = c^2

Take the square root of each side

sqrt(225) = sqrt(c^2)

15 =c

the first option is the answer.