use (size old tv)*sqrt(337)/15 to find the size of the hdtv with the same height as the old tv

you gotta be friggin kidding me?

the real formula is \[\sqrt{(1+r_h^2)\frac{d_s^2}{1+r_s^2}}\] where r_h is the hd ratio 16:9, r_s is the sd ratio 4:3, and d_s the sd size

this finds the height of the sdtv and then finds the diagonal size of the hdtv with that same height

I was thinking mayybe a 42"... but I'll need at least a 44" so I can watch all my Murder She Wrote reruns.

42" is big enough for me... and I'm finally getting to enjoy the hd aspect of things with my ps3/bluray player