To solve this you must use Pythagorean theorem:
a and b are the legs (the sides that form a perpendicular/right angle)
c is the hypotenuse (the side opposite the right angle)
In this case...
a = 8 cm
b = 6 cm
c = x
^^^Plug these numbers into the theorem
simplify
64 + 36 =
100 =
To remove the square from x take the square root of both sides to get you...
√100 = x
Which is when simplified:
(choice C)
10 cm
Hope this helped!
~Just a girl in love with Shawn Mendes