(adsbygoogle = window.adsbygoogle || []).push({}); cant work this out, why is it happening, please help!!

y(t)=22t-4t[tex]^{2}[/tex]

x(t)=30t-t[tex]^{3}[/tex]

find x(y) or y(x)

what i did was say

y-22t+4t[tex]^{2}[/tex]=0

t=[tex]\frac{22+\sqrt{484-16y}}{8}[/tex]=[tex]\frac{11+\sqrt{121-4y}}{4}[/tex]

x=30*[tex]\frac{11+\sqrt{121-4y}}{4}[/tex]-([tex]\frac{11+\sqrt{121-4y}}{4}[/tex])[tex]^{3}[/tex]

which works for every value for y(t) i plug in except for t=2s

where i get, from the original equations, x=52 y=28

but from my equation when y=28, x=62.125

why is this happening?

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# Homework Help: Cant work this out, why is it happening, please help

**Physics Forums | Science Articles, Homework Help, Discussion**