Question

Can someone help me with all these

Answer 1

1) factorise the expression: 2(x^2-4x) + 1 = 2(x-2)^2 - 8 + 1 = 2(x-2)^2 -7 so the answer is c
2) formula of the circle will be (x-2)^2 + y^2 = 2^2 which expands to x^2 -4x + 4 + y^2 = 4 which simplifies to x^2 + y^2 -4x = 0 so b
3) d
4)a
5)d
6)b

Answer 2

I don't know
I think for number 6 the answer is. A