Math problem; help please?

Question

Write y=x^2+8x-4 in vertex form and identify the vertex.

Having a little trouble with this problem....If you could tell me the answer and explain your work, that would be great, so I understand it for the others. Thanks.

Answer 1

y+4=x(x+8)

(remember the for i showed u yday)

vertex = -8,-4

i might be wrong though

Answer 2

Complete the square on the right side:

y = x² + 8x + (8/2)² - (8/2)² - 4

y = x² + 8x + 16 - 16 - 4

y = (x + 4)² - 12

From this we read off that the vertex is at (-4, -20)

Answer 3

uhhh... this is math?