Answer:
27.5
Explanation:
first you find what 30x30 is as A squared plus B squared is equal to C squared. your A is 12 and your C is 30.
so!
30x30 is 900
12x12 is 144
subtract 144 from 900 and you get 756. once you find the square root you get 27.49. then round up to 27.5