SOLUTION: find dy/dx x=9/t y=t-t^2 I got as far as: dx/dt=-9t^-2 and dy/dt=1-2t dy/dx:1-2t/-9t^-2 is incorrect thank you for your help.

Algebra ->  Test -> SOLUTION: find dy/dx x=9/t y=t-t^2 I got as far as: dx/dt=-9t^-2 and dy/dt=1-2t dy/dx:1-2t/-9t^-2 is incorrect thank you for your help.      Log On


   

Question 885296: find dy/dx
x=9/t
y=t-t^2
I got as far as: dx/dt=-9t^-2 and dy/dt=1-2t dy/dx:1-2t/-9t^-2 is incorrect
thank you for your help.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
This method may be different than what is expected and maybe this is non-standard, but if you want dy/dx, maybe try to eliminate t?

x=9%2Ft
t%2F9=1%2Fx
t=9%2Fx
-
y=t-t%5E2
y=9%2Fx-81%2Fx%5E2----- equation in only x and y. FIND DERIVATIVE OF THIS? Find the derivative based on this equation.