Using the focus and directrix to find the equation of a parabola | Algebra II | Khan Academy

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[pauluk]

I know its an exercise-answer (only one correct answer) but the applet would work better with a 'trace' function on the foot of the altitude segment as otherwise you are merely 'imagining' the true path which it follows, or (even better) to be able to draw its locus dynamically.


I like how James Tanton does problems on his channel: He will ask about five different questions of the same picture or set up at once and allow the student to 'nut it' by answering them in free-style order

[DelphianSociety]

Some suggestions for future series: Fourier transforms/series and partial differential equations

[seonghwanshin]

Khan Academy Where can I actually find the webpage that has a similar problem like this in khanacademy.com?

[JuanGutierrez-nggs]

what website is used onscreen to display the problem?

[jamesherring]

Sal you could have just used the vertex on the graph to find the x, y values without any algebra at all

[amazingwow]

For the people who say this video sucks or was confusing, your the problem. This is a great video, good intuition.

[aayushikamra]

it contradicted at a you calculated y for (x, y) you did subtract (-3/8) from it and made it (y-(-3/8) to (y+3/8) but when it came to calculating the distance of directrix to (x, y) you just added it made it (y+5/8), rather it should be clear my doubt

[saniaansari]

Thanks for the video but I'm still confused. Nvm

[chestercarbungco]

why the h 3/4 pop up it really destroy entire video