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UrbanXrisis
Nov2-04, 08:09 PM
if:
x=4.28t+0.181
y=6.47t^2+4.51t+0.455

what is equation of the graph of y vs x?

I lost all my data for this physics project and all I have left are these notations. I would be able to find an equation if I had my graph. Any help would be appreciated.

-UX

Pyrrhus
Nov2-04, 08:38 PM
those are parametric equations isolate t, then substitute in the other, and graph it.

UrbanXrisis
Nov2-04, 08:46 PM
I didn't catch that, can you explain it in more detail?

Leong
Nov2-04, 08:52 PM
I think he means that find t in term of x and subsitute the t into the second equation of yours.

Pyrrhus
Nov2-04, 08:54 PM
sorry, i was away, yes what leong said.

UrbanXrisis
Nov2-04, 08:54 PM
ahh...so it's similar to a system of equations

CeeAnne
Nov3-04, 12:04 AM
Urban, the graph of the equations would be a parabola. I'm not real good at math but I think you can graph the equation by substituting values for t in both equations and evaluating to get the x and y points for each value of t. For instance, for t=0, x=0.181 and y=0.455 ... for t=1, x=4.461 and y=11.435 ... for t=2, x=8.741 and y=35.355 and so on for as many + and - values of t as you need. Plot the points and connect them as a smooth curve.

HallsofIvy
Nov3-04, 07:15 AM
Urban, the graph of the equations would be a parabola. I'm not real good at math but I think you can graph the equation by substituting values for t in both equations and evaluating to get the x and y points for each value of t. For instance, for t=0, x=0.181 and y=0.455 ... for t=1, x=4.461 and y=11.435 ... for t=2, x=8.741 and y=35.355 and so on for as many + and - values of t as you need. Plot the points and connect them as a smooth curve.
Yes, but that's irrelevant to the question asked.

CeeAnne
Nov6-04, 11:44 PM
Well, Ivy, I don't believe it is irrelevant. Urban did say the equation could be found with the graph and any help would be appreciated.