{"issue":{"state":"open","created_at":"2011-11-23T02:25:00Z","updated_at":"2011-12-04T23:43:10Z","comments":1,"user":{"gravatar_id":"96ea3904626fe17bec2152ee31cee0cd","id":924247,"url":"https://api.github.com/users/KhanBugz","login":"KhanBugz","avatar_url":"https://secure.gravatar.com/avatar/96ea3904626fe17bec2152ee31cee0cd?d=https://a248.e.akamai.net/assets.github.com%2Fimages%2Fgravatars%2Fgravatar-140.png"},"body":"Reporter: tiwoc@arcor.de\n\nFocus is (1, 3/8), Directrix is y=5/8.\n\nThe solution should be y-1/2 = -2*(x-1)^2.\n\nHowever, the value for y_1 is not accepted. In the error text, it says: \"So x_1 = 1. And y_1 = (3/8+5/8)/2 = 1\". This is clearly wrong as (3/8+5/8)/2 = 1/2.\n\n[parabola_intuition_3.html?seed=174&problem=0](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/parabola_intuition_3.html?seed=174&problem=0&debug)\n\n[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/parabola_intuition_3.html?seed=174&problem=0&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5B%5C%221%2F2%5C%22%2C%5C%22-2%5C%22%2C%5C%221%5C%22%2C%5C%220.5%5C%22%2C%5C%220.375%5C%22%2C%5C%220.625%5C%22%5D%22%2C68%5D%2C%5B%22hint-activity%22%2C%220%22%2C0%5D%2C%5B%22hint-activity%22%2C%220%22%2C0%5D%2C%5B%22hint-activity%22%2C%220%22%2C0%5D%2C%5B%22hint-activity%22%2C%220%22%2C0%5D%2C%5B%22hint-activity%22%2C%220%22%2C0%5D%2C%5B%22hint-activity%22%2C%220%22%2C0%5D%2C%5B%22hint-activity%22%2C%220%22%2C0%5D%2C%5B%22hint-activity%22%2C%220%22%2C0%5D%5D)\n\n    [[\"1/2\",\"-2\",\"1\",\"0.5\",\"0.375\",\"0.625\"]]\n\nMozilla/5.0 (X11; Linux x86_64) AppleWebKit/535.1 (KHTML, like Gecko) Ubuntu/11.10 Chromium/14.0.835.202 Chrome/14.0.835.202 Safari/535.1\n\nMathJax is loaded, ready, queue length: 0\n\n","assignee":null,"id":2325859,"labels":[{"color":"e102d8","name":"chrome","url":"https://api.github.com/repos/Khan/khan-exercises/labels/chrome"},{"color":"FFA500","name":"wrong-or-unclear","url":"https://api.github.com/repos/Khan/khan-exercises/labels/wrong-or-unclear"}],"number":6948,"pull_request":{"patch_url":null,"html_url":null,"diff_url":null},"title":"Parabola intuition 3 - Wrong calculation for Parabola","closed_at":null,"html_url":"https://github.com/Khan/khan-exercises/issues/6948","url":"https://api.github.com/repos/Khan/khan-exercises/issues/6948","milestone":null},"action":"created","comment":{"created_at":"2011-12-04T23:43:10Z","updated_at":"2011-12-04T23:43:10Z","user":{"gravatar_id":"91e2e1c5cda628431f62bdaa980b8cd6","id":1017630,"url":"https://api.github.com/users/beneater","login":"beneater","avatar_url":"https://secure.gravatar.com/avatar/91e2e1c5cda628431f62bdaa980b8cd6?d=https://a248.e.akamai.net/assets.github.com%2Fimages%2Fgravatars%2Fgravatar-140.png"},"body":"duplicate #6204","id":3009843,"url":"https://api.github.com/repos/Khan/khan-exercises/issues/comments/3009843"}}