We have this take home quiz and there is one part I don't understand, in the quiz he tells us to "determine the equation of a circle with a center at (-2,3) and passing though the origin" but he doesn't give us the radius. I have no idea how to solve this, I mean I got completely lost after (x-(-2))^2 + (y-3)^2 = r^2
If you know the center is at (-2,3) and you know the circle passes through the origin (0,0), you know the radius. It is just the distance from the center to the origin. radius=sqrt((-2)^2+3^3)
My guess is that the center of the circle is (-2,3). The origin is (0,0). So, it would seem that you would create a triangle and use the pythagorean theorem to solve for the radius . So the radius should be square root of 13? It has been a long time since I have done trig.
you use the equation of the circle format [ r^2 = (x-h)^2 + (y-k)^2] h is -2 k is 3 r (as shown earlier) is sqrt 13. Therefore, EofaC is 13 = (x+2)^2 + (y-3)^2
Thanks for everyones help. I have a new question though, what the hell is the Axis Of Symmetry and how do you figure it out?
In the era of the "information superhighway", why are you looking for answers on this basketball cul-de-sac? Google turns up a bunch of links explaining "axis of symmetry". Here's one: http://www.mathwords.com/a/axis_symmetry.htm
Classic. You're all failing the real tests, so they decide to let you cheat on the take home quizzes. Now that's education!!
I'm not failing, the teachers test are just notoriously hard. Hell even he thinks 80-85% on one of his tests is a good grade and I typically get something around there, maybe a little lower.
That isn't a hard test. I had a physics professor that would make his tests so hard that with the curve, a 30% would be an A.
LOL, that reminds me of an Asset Pricing class I took where I didn't get a single answer right and still got a B+.
I took "Physical Chemistry", which was calculus-based chemistry (determining a position of a molecule, eigenfunctions, blah blah blah etc) my junior year. that shit was so fucking abstract and fucked up, I had no idea what the fuck was going on...still got a B+ in that class. weird shit. dunno how i pulled that off, i think it was because it was all based on a curve?
