Parabola with Focus (-5,0) & Vertex (-5,-4): Find Equation

AI Thread Summary
To find the equation of the parabola with a focus at (-5,0) and a vertex at (-5,-4), the correct form is derived from the standard equation for parabolas with vertical axes. The vertex form is y = a(x - h)² + k, where (h,k) is the vertex. The distance from the vertex to the focus determines the value of 'a', which is crucial for the equation. The initial equation proposed, x² + 10x + 16y + 89 = 0, is incorrect, and further steps are needed to derive the correct equation. A step-by-step approach is recommended to verify the calculations and ensure accuracy.
TonyC
Messages
86
Reaction score
0
Fins an equation for the parabola with focus at (-5,0) and vertex at (-5,-4).

I have come up with:

x^2 + 10x + 16y + 89 = 0

How far off am I?
 
Physics news on Phys.org
TonyC said:
Fins an equation for the parabola with focus at (-5,0) and vertex at (-5,-4).

I have come up with:

x^2 + 10x + 16y + 89 = 0

How far off am I?

Can't you check for yourself?

Is it a parabola? (That's easy- there is an x2 term but no y2 term.)

What is the vertex? (Solve for y, then complete the square.)

What is the focus? (You will need to know the equation for the focus of a given parabola.)
 
That is what I am having trouble determining. Can you show me step by step how to check myself?
 
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Back
Top