If a particular radio telescope is 100ft in diameter and has a cross section modeled by the equation x^2=167y, how deep is the parabolic dish? What is the location of the focus? can someone help me with this?

Question

amistre64 · Answer

learned a bit more about this stuff today i did....

amistre64 · Answer

x^2 = 4ay  where a is the distance from the vertex.....  and your vertex is at 0,0

amistre64 · Answer

167/4 is a  so the focus is at..... 0+ 167/4

anonymous · Answer

right. i have that its the first part that im having trouble with

amistre64 · Answer

ok.....we know that it 100 feet across, so that is 50 feet in both directions, when y = 50, what is x^2 = ?

amistre64 · Answer

is it headed in the x direction or the y?

anonymous · Answer

the parabola opens up

amistre64 · Answer

then I would turn it into the normal way of viewing this:

y =(1/167)x^2.  when x = 50, whats y=?

amistre64 · Answer

2500/167...

anonymous · Answer

so thats how deep it is?

amistre64 · Answer

yup,...

amistre64 · Answer

the numbers are the same, we just repositioned them into the "normal" way that this equation would look.

amistre64 · Answer

the vertex is at (0,0) thats half way, half of the diameter is 50...plug it in :)

amistre64 · Answer

14.97 is what I get

anonymous · Answer

k I'll try that. thanks!

amistre64 · Answer

youre welcome :)

amistre64 · Answer

have you ever worked with quadratic equations?

amistre64 · Answer

cause thats all a parabola is...

anonymous · Answer

yes. im in pre calc at a jr college, this stuff is being thrown at me quick but im doing my best.

amistre64 · Answer

phcc sound familiar to you?

anonymous · Answer

no whats that?

amistre64 · Answer

its the community college I go to right now :)  just wondering if you were in my trig/pre calc class ....

anonymous · Answer

na im at tcc

amistre64 · Answer

well, good luck to ya :)

anonymous · Answer

thanks!