Answer:
c= 18.4
Explanation:
Since this is a right triangle, we can use trig functions
cos theta = adj/ hyp
cos theta = a/c
cos 57 = 10/c
Multiply each side by c
c cos 57 =10
Divide each side by cos 57
c = 10/cos 57
c=18.36078459
Rounding to the nearest tenth
c= 18.4