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anonymous
 one year ago
Find the standard form of the equation of the parabola with a focus at (8, 0) and a directrix at x = 8.
anonymous
 one year ago
Find the standard form of the equation of the parabola with a focus at (8, 0) and a directrix at x = 8.

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triciaal
 one year ago
Best ResponseYou've already chosen the best response.0dw:1433220174652:dw

triciaal
 one year ago
Best ResponseYou've already chosen the best response.0@jim_thompson5910 please verify

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0The parabola will open to the left side, so it will have a y^2 term (instead of an x^2 term)

triciaal
 one year ago
Best ResponseYou've already chosen the best response.0not use to those so the vertex is (0,0)

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0dw:1433217367354:dw

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0dw:1433217380478:dw

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0dw:1433217399104:dw

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0dw:1433217436087:dw

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0I'm using the ideas shown here http://www.mathwords.com/f/focus_parabola.htm 4p(xh) = (yk)^2 4*8(x0) = (y0)^2 32x = y^2 x = (1/32)*y^2 x = (1/32)*y^2 ... the coefficient is made to be negative so the parabola opens to the left (instead of right) dw:1433217556903:dw

triciaal
 one year ago
Best ResponseYou've already chosen the best response.0so is the equation I have wrong ?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0anything with x^2, and not y^2, will open upward or downward

triciaal
 one year ago
Best ResponseYou've already chosen the best response.0I actually have the same diagram see above (not as neat )

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0I see it, but again, you'll have y^2 instead of x^2

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0http://images.flatworldknowledge.com/reddenint/reddenintfig08_009.png

triciaal
 one year ago
Best ResponseYou've already chosen the best response.0dw:1433221628889:dw

triciaal
 one year ago
Best ResponseYou've already chosen the best response.0you are saying since I have the directrix vertical instead of horizontal then the value from f to v is the y component?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0because the directrix is vertical, this means that the parabola will open to the left or right https://dr282zn36sxxg.cloudfront.net/datastreams/fd%3A7980ac3c31917d6d9238e3fe5ee79be178774387290a21eba7ba82d2%2BIMAGE%2BIMAGE.1

triciaal
 one year ago
Best ResponseYou've already chosen the best response.0got that not the problem what I am missing is how to write the equation

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0http://www.mathwords.com/f/focus_parabola.htm you use 4p(xh) = (yk)^2 since the parabola opens to the left, p < 0 based on that previous image. So p = 8 (h,k) = (0,0) is the vertex

triciaal
 one year ago
Best ResponseYou've already chosen the best response.0@jim_thompson5910 thank you so much !!! I will look at the links guess better try to learn that version of the equation thank you

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So what would the finally equation be?

triciaal
 one year ago
Best ResponseYou've already chosen the best response.0follow what Jim had above. I am used to the other format and in addition I had my x and y switched since it opened left, sorry

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.0It depends on what format they want it in, but you could go with something in the form x = ay^2 + by + c
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