InterviewSolution
Saved Bookmarks
| 1. |
Find the foci of the ellipse `25(x+1)^2+9(y+2)^2=225.` |
|
Answer» Correct Answer - `(-1,2)(-1,-6)` The given equation can be wirtten as `((x+1)^(2))/(9)+((y+2)^(2))/(25)=1` which represents an ellipse whose center is `(-1,-2`) and semi-major and the minor are 5 and 3, respectively. The eccentricity of the ellipse is given by `9=251-e^(2)or e=(4)/(5)` Shifting the origin at (-1,-2), the given reduces to `(x^(2))?(9)+(y^(2))/(25)=1" "(1)` where `x=X-1,y=Y-2" "(2)` The coordinates of the foci (1) are `(X=0,Y=+-be)`, where `b=5, e=4//5, i.e., the foci of (1) (X=0,Y+-4)`. Therefore, the cooridnates of the foci of the given ellipse are (-1,-2) and (-6,-6) |
|