Question

find the vertex of the parabola f(x)=-2x^2-8x-9

Answer 1

convert is to a(x-h)^2+k form

Answer 2

(h, k) is the vertex

Answer 3

what is a?

Answer 4

a, h, and k are constants

Answer 5

isn't h=x and k=y?

Answer 6

yes

Answer 7

is a -2?

Answer 8

if you want the answer, it's (-2, -1)

Answer 9

well, I've got the answer, I just don't know how to work it

Answer 10

have you learnt completion of square

Answer 11

yes

Answer 12

ok, I can do it that way?

Answer 13

yes

Answer 14

I'm not very good at completing the square though. I got x=-1/2

Answer 15

keep doing it

Answer 16

how do I take it further?

Answer 17

do I plug that in for x and solve for something else?

Answer 18

No, just redo the completion of square

Answer 19

I must have missed something haha