Finding the Standard Equation for the Ellipse with Given Vertices and Foci

  • Thread starter Thread starter iheartmydog
  • Start date Start date
  • Tags Tags
    Ellipse Section
Click For Summary
SUMMARY

The standard equation for the ellipse with vertices at (-2,-5) and (-2,4), and foci at (-2,-4) and (-2,3) is derived as follows: the equation takes the form (x-h)²/b² + (y-k)²/a² = 1, where the center is located at (-2, -0.5) and the semi-major axis length a is calculated to be 4.5. The relationship between the semi-major axis a, the distance to the foci c, and the semi-minor axis b is crucial for completing the equation. The calculated values confirm that the major axis is vertical, consistent with the given foci and vertices.

PREREQUISITES
  • Understanding of conic sections, specifically ellipses
  • Familiarity with the standard form of the ellipse equation
  • Knowledge of the relationship between the semi-major axis, semi-minor axis, and foci
  • Basic algebra skills for manipulating equations
NEXT STEPS
  • Review the properties of ellipses in conic sections
  • Study the derivation of the ellipse equation from given vertices and foci
  • Learn about the relationship between a, b, and c in ellipses
  • Practice solving similar problems using different sets of vertices and foci
USEFUL FOR

Students studying algebra or geometry, educators teaching conic sections, and anyone looking to deepen their understanding of ellipse equations and their properties.

iheartmydog
Messages
1
Reaction score
0

Homework Statement



Find the equation for the conic ellipse with vertices (-2,-5) (-2, 4) and foci (-2,-4) (-2,3)

Homework Equations



I want to make sure I am solving the problem correctly

The Attempt at a Solution



(x+2)^2/8 + (y+0.5)^2/20.25 =1
 
Physics news on Phys.org
Here is some help.

Standard equation for the ellipse you describe begins this way:
(x-h)^2/b^2+(y-k)^2/a^2=1,
and a is the semi-major axis length, and a>b. You gave focus points which are on the line, x=-2, and so consistent with the given major axis being vertical. Checking the vertices you find the value for a is |-5-(4)|*(1/2)=4.5,
a=4.5

You also find that based on the foci, the center of your ellipse is at x=-2 and y=(-4+3)*(1/2)=-(1/2); or the point for center is (-2, -1/2).There is a fairly well known relationship between a, c, and the minor axis length b. I leave finding this and the rest of the work to you. A review from a college algebra or intermediate algebra textbook will be very helpful. Give a try first before more help is given - if any needed.

Checking your results again, it seems you mostly or entirely have the right idea; your center point reads correctly in your equation, at least.
 

Similar threads

Replies
4
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 7 ·
Replies
7
Views
5K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 10 ·
Replies
10
Views
4K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K