Answer:
Correct Answer is A. 3 times root 5.
Step-by-step explanation:
We all know that in a right angled triangle, the square of both sides is equal to the square of hypotension.
hence,
a^2 + b^2 = c^2
a^2 + (2)^2 = (7)^2
a^2 + 4 = 49
a^2 = 49-4
a^2 = 45
a = root of 45 which is 6.7082
which can be written as 3 times root 5
