Answer:
C) 8 km
Explanation:
x is another leg next to 6.
10 is the hypotenuse.
a^2 + b^2 = c^2
a & b are legs and c is the hypotenuse.
x^2 + 6^2 = 10^2
x^2 + 36 = 100
x^2 = 100 - 36
x^2 = 64
√x^2 = √64
x = 8
P.S It may look just slightly different, but your teacher or the program did not make it up to scale.
Hope This Helps! •v•