Identify the vertex and axis of symmetry of 8x

Factor the minus or negative off the -x²+8x and don't do anything with -12

Find the number that can complete the square, for x²-8x, it'd be +16.

Just think of debt, you borrow, you have to give back. You borrow +16 then you have to give 16 out so you write -16 out of x²-8x+16 but still inside the bracket.

Distribute the minus/negative inside the bracket as you get -(x-4)²+16-12 because negative multiply negative and you get positive

Then you get y=-(x-4)^2+4

Because a<0, it's inverted parabola as shown below.

therefore, the vertex is at (4,4) or (-(-4), 4) because the vertex is at (-h,k) and h is -4 that means -h = 4

axis of symmetry is -b/2a, our b is 8, -b = -8 and 2a = 2(-1) so -8/-2 = 4 (From the standard form)

therefore, axis of symmetry is 4

the answer is ! ?

answer 1 : option "c"

answer 2 : option "d"

answer 3 : option "b"

answer 4 : option "d"

answer 5 : option "b"

answer 6 : option "a"

answer 7 : option "c"

answer 8 : option "d"

answer 9 : option "c"

answer 10 : option "d"

answer 11 : option "c"

answer 12 option "b"

answer 13 option "c"

answer 14 option "c"

answer 15 option "d"

answer 16 option "a"

answer 17 option "b"

answer 18 option "c"

answer 19 option "a"

answer 20 option "a"

answer 21 option "c"

d