Answer:
1. D 2. B 3. C
Explanation:
WARNING: I am not 100% sure about 2.
1. If you simplify the first part of the equation for letter D, you'll realise it is the same equation.
2. It is either B or D. I believe it is B because you would not have to multiply 4 again.
3. The square root of 121 is eleven, the square root of x^2 is x. x=11.