SOLUTION: {{{4y^2-4y-4x+5=0}}} How do I write that in standard form? I've tried many ways.

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Question 830525: 4y%5E2-4y-4x%2B5=0
How do I write that in standard form? I've tried many ways.

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
4y%5E2-4y-4x%2B5%22%22=%22%22%220%22

You want it to look like this

%28y-k%29%5E2%22%22=%22%224p%28x-h%29

which is a parabola with a horizontal axis of symmetry that
either opens left or right. We can't tell which yet.  It
has a vertex of (h,k)

4y%5E2-4y-4x%2B5%22%22=%22%22%220%22

Get the y-terms on the left and everything else on the right

4y%5E2-4y%22%22=%22%224x-5

Divide every term by 4

y%5E2-y%22%22=%22%22x-5%2F4

Complete the square on the left side:

1. To the side, multiply the coefficient of y, which is -1, by 1%2F2,
   getting -1%2F2
2. Square the result of 1.  %28-1%2F2%29%5E2=1%2F4
3. Add the result of 2 to both sides of the equation:

y%5E2-y%2B1%2F4%22%22=%22%22x-5%2F4%2B1%2F4

Factor the left side:  %28y-1%2F2%29%28y-1%2F2%29=%28y-1%2F2%29%5E2
Combine the numbers on the right -5%2F4%2B1%2F4=-4%2F4=-1

%28y-1%2F2%29%5E2%22%22=%22%22x-1

To show the 4p in the standard equation, perhaps your teacher
wants you to put a 1 factor on the right side:

%28y-1%2F2%29%5E2%22%22=%22%221%28x-1%29

and now it corresponds exactly to

%28y-k%29%5E2%22%22=%22%224p%28x-h%29

The vertex is (h,k) = (1,1%2F2)

4p=1, so p=1%2F4, since p is positive it opens right.

Its focus is the point 1%2F4 unit right of its vertex,
at (1,3%2F4), and the latus rectum is 4p=1 unit long
through the focus.  The directrix line is the vertical 
line 1%2F4 unit left of the vertex.  It has the 
equation x=3%2F4. to 4p = 1 unit. So we draw the 
vertex, focus, directrix and latus rectum and we have this:



Then we sketch in the parabola:



Yes, I know you didn't need to graph it but you'll have to later.

Edwin