How do i turn y = ax2 + bx + c to (h, k) .
and how do i turn (h, k) to ax2 + bx + c

Question

How do i turn y = ax2 + bx + c to (h, k) .
and how do i turn (h, k) to ax2 + bx + c

anonymous · Answer

help

amistre64 · Answer

what does (h,k) signify?

anonymous · Answer

the vertex

amistre64 · Answer

oh, then it makes sense now

amistre64 · Answer

the vertex is olong the axis of symmetry defined to be:  x = -b/(2a)

amistre64 · Answer

or are you trying to convert it to  a(x-h)^2 + k  algebraically?

anonymous · Answer

algebraically

campbell_st · Answer

(h, k) is the vertex, I'd expect... 

so group the terms in x and then complete the square

here is an example

$$y = x^2 + 6x - 7$$

complete the square in x

$$y = (x^2 + 6x + 9) - 7 - 9$$

adding 9 makes a perfect square in x, but to keep the equation in balance 9 also needs to be subtracted. 

so it becomes 

$$y=(x + 3)^2 - 16$$

with vertex at (-3, -16)         so h = -3 and k = -16

hope it helps

amistre64 · Answer

simplest thing to do is expand it out and compare parts

a(x^2 -2xh + h^2) + k

ax^2 -2axh + ah^2 + k

-2ah = b

ah^2+k = c

anonymous · Answer

where the 9 come from

amistre64 · Answer

by comparison

h = -b/(2a)

k = c - ah^2
  =  c -ab^2/(4a^2)
  =  c -b^2/(4a)
  =  (4ac -b^2)/(4a)

anonymous · Answer

still confused, anyone got a video or something

amistre64 · Answer

you tube completing the square if thats what helps you learn the best

anonymous · Answer

jow did u get from
(x2+6x+9)
to
(x+3)2

anonymous · Answer

how