Question

Each one of these answers is incorrect. State why the answer is incorrect, the correct answer, and what property of indices is used.

Answer 1

What subject is this?

The first one is correct
Second correct
third incorrect. 

Hope this helped

Answer 2

The first one is incorrect because (4x)^2 is the same as 4x^2 and not 8x^2.
2(4x)^2=8x^2 would however, be right.

The second one is incorrect because a number squared can never be negative as a negative* a negative is always a positive, a correct answer would be: 3^2=9

The third one is incorrect because 6/12=0.5 not 2, a correct answer would be:
12x^8/6x^4=2x^4

Hope this helps :)