SOLUTION: Write the equation of the directix of the conic section shown below: y^2-4x+4y-4=0 (please help, thank you)

Algebra.Com
Question 968532: Write the equation of the directix of the conic section shown below:
y^2-4x+4y-4=0

(please help, thank you)

Answer by josgarithmetic(39621)   (Show Source): You can put this solution on YOUR website!
Skipping the fundamental derivation, but for directrix (-p,y) using p as a positive number, focus (p,0), for parabola in standard form a axis of symmetry being the x-axis, equation is . If vertex were some point (h,k), then the equation of this parabola is .

Your example problem equation is easily transformed into . You can make the correspondances to find p=1 IF you had parabola in standard form and standard position, but your case is that vertex is pushed to the left by 2 units. See, your vertex is (-2,-2); your directrix is , or simply now .

Remember, p was taken as nonnegative in the fundamental derivation for standard position, so directrix is p units to the left of the vertex point, and vertex would be on the origin.

RELATED QUESTIONS

Write the equation of the directrix of the conic section shown below. Write your answer... (answered by Fombitz)
Please help me!! directions: Identify the conic section represented by the eqation by... (answered by stanbon)
PLEASE HELP!!! IM SO CONFUSED!!! Thank you! Write the standard equation of this conic (answered by lwsshak3,ewatrrr,josmiceli)
classify the conic section defined by the equation. write the standard equation of the... (answered by stanbon,ayshia)
What conic is described by the equation 4x^2 + 4y^2 - x + y = 0. Please show steps. Thank (answered by Gogonati)
Identify the conic section and write the standard form of the equation... (answered by scott8148)
Identify the conic section and write the standard form of the equation... (answered by scott8148)
Can someone pretty please help me figure this out? For the following equation of a... (answered by Theo)
Can you please help me with a problem? i have to identify the conic section and write the (answered by lwsshak3)