Engineering Board Exam Reviewer · Parabolas · medium

A parabola has its vertex at the origin, opens to the right, and passes through (2,4). Find the length of its latus rectum.

1. 4
2. 16
3. 8
4. 2

Answer

C. 8

Solution

y2=4px: 16=4p(2) p=2. The latus rectum is 4p=8.

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