Engineering Board Exam Reviewer · Parabolas · medium

The point (4,4) lies on the parabola y2=4x. Find its distance from the focus.

1. 3
2. 4
3. 6
4. 5

Answer

D. 5

Solution

The focus is (1,0). d=sqrt((4-1)2+(4-0)2)=5 (which also equals x+p=4+1).

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