Engineering Board Exam Reviewer · Ellipses · hard

Find the distance from the center of the ellipse x2/25+y2/9=1 to each directrix.

  1. 16/5
  2. 5/4
  3. 9/5
  4. 25/4

Answer

D. 25/4

Solution

e= 45 and the directrices are x= /e= 5/4/5= 25/4= 6.25.

More Ellipses questions

  1. Find the area of the largest rectangle that can be inscribed in the ellipse x2/25+y2/9=1.
  2. Find the distance between the foci of the ellipse 4x2+9y2-16x+18y-11=0.
  3. Find the equation of the ellipse with center at the origin, vertices at ( 6,0) and a minor axis of length 8.
  4. A point on the ellipse 4x2+9y2=36 has x=2 and y>0. Find its y-coordinate.
  5. The major axis of an ellipse is twice its minor axis. Find the eccentricity.
  6. Find the area enclosed by the ellipse x2/16+y2/9=1.
  7. For any point on the ellipse 9x2+25y2=225, find the sum of its distances from the two foci.
  8. Find the foci of the ellipse (x-2)2/25+(y+1)2/9=1.
  9. Find the length of the latus rectum of the ellipse x2/36+y2/20=1.
  10. Find the equation of the ellipse with foci at ( 3,0) and a major axis of length 10.

All Ellipses questions