Recent content by oray

Thanks for your help! I wasn't familiar with a lot of the terminology you used (sophomore in high school) but I think I mostly understood what you were saying. Here's what I came up with (let me know if I got it right/wrong): http://img691.imageshack.us/img691/7160/2ddrawing.png

Homework Statement I'm having trouble drawing a wedge-and-dash, 2 dimensional molecular structure for Vitamin C (ascorbic acid). All of the diagrams I've looked at (on the Wikipedia page, and some .edu websites) are incomplete: they either don't include the carbon and/or hydrogens molecules, or...

Homework Statement You start with 10.00 g of sand/salt mixture. suppose you end up with 4.52g of sand and 5.9g of salt. a) calculate the % sand and salt based only on the sand result: "4.52 g sand means there must have been 5.48g of salt" b) do the same using only the salt result: "5.9g salt...

BUMP! GAH i have 24 minutes to complete this :(

how? it has 2 exponents meaning its a hyperbola, circle, or ellipse, and the denominators are the same making it a circle? right?

ok. so how do i calculate the range without a calculator?

AH got it. 2x^2+2y^2=9 x^2=16-4y^2 x^2/16 + y/25 =1 3x^2 =7 + 3y^2 x/16 + y/25 = 1 x^2 = 16 - (y-3)^2 circle. circle. parabola. hyperbola. line. circle. brilliant!

Homework Statement (1/(x+7))-5 find the domain and range. im having trouble graphing this one on my calculator, because when i zoom out the graph looks a lot different than when i zoom in. i think i have an answer though, so i need a quick check. domain: none (infinite) rangE: 0 to -10?

i did, and edited my answers. one thing i wasnt sure about was something like this: 3x^2 =7 + 3y^2 are we assuming u subtract 3y^2 from both sides so u get: 3x^2 - 3y^2 =7 which looks like the formula for a hyperbola? anyway, someone please check my answers. thanks!

im confused. can someone walk me through this step by step? i can keep guessing but i don't have much time and i need to figure this out. so can someone offer some guidance? thanks :) EDIT after looking through my textbook I've changed my answers 2x^2+2y^2=9 CIRCLE x^2=16-4y^2 PARABOLA...

ok here's what i came up with... 2x^2+2y^2=9 CIRCLE x^2=16-4y^2 CIRLCE x^2/16 + y/25 =1 ELLIPSE 3x^2 =7 + 3y^2 ELLIPSE x/16 + y/25 = 1 PARABOLA. did i get them right? i really need confirmation asap thanks for all the help guys!

Homework Statement when asked to identify an equation as a parabola, hyperbolas, ellipses, circles, straight lines, or none of the above, how can i deduce which is which? the problems given are: 2x^2+2y^2=9 (im pretty sure this one's a circle, just by graphing it, but id like...

awesome. figured it out. thanks for all the help people :)

okay... (x^2-2y^2+9)=25 -(x^2+y^2)=25 -3y^2+9=0 -3y^2=-9 y^2=-3 y=null?

huh? I am confused? what is the RHS? i really am confused on where to start in general.