Posted by **Natalia** on Sunday, November 30, 2008 at 3:02pm.

Thanks to those who helped with my question: y+3=-1/12(x-1)^2. The only thing I am still unsure of is how to write the equation for the directrix. Do I just simply write 0=3-3, (the values plugged in for y=k-p). Thanks again for your help!!

- Algebra -
**Natalia**, Sunday, November 30, 2008 at 3:03pm
Whoops and one thing I forgot. Is it allowed for a parobala to open upward and have the directrix intercept it? Since p is greater than zero, it would have to open upward, but then the directrix would intercept the parobala (the directrix follows the x axis, and is at zero y)

- Algebra -
**Damon**, Sunday, November 30, 2008 at 3:09pm
p = Negative. (I called p a but same difference)

I showed you that this parabola opens downward in my explanation of the axis of symmetry at x = 1

the directrix is a horizontal line (m=0)

y = 0 x + 0

or

y = 0

## Answer this Question

## Related Questions

- algebra - A few more question Id like for someone to check please. 1) what are ...
- Algebra II - Write an equation for the parabola with focus (1,3) and vertex (0,3...
- algebra - How would one write the equation of a parabola whose directrix is y=-6...
- Algebra - I am supposed to write the standard equation of the parabola with the ...
- algebra 2 - Directions: The focus and directrix of a parabola are given. Write ...
- Pre-Algebra - this is the question please help me explain what to do its ...
- math ,hep, plz - can someone help explain this for me please... Problem #1 What ...
- pre-algebra - write an inequality for the sentence. The total t is greater than ...
- can someone help me with a question of an explanat - my question is for math, I ...
- Math - Can someone correct them 5) Write fraction as a percent 7/8 My answer: 0....