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## #1 Re: Help Me ! » polar points in rectanglular coordinates » 2006-03-11 12:53:58

Thank you Mikau,

Your post was incrdibly helpful! I understand it all now thank you for doing the diagrams also.

Kind Regards

Lakitu

## #2 Help Me ! » polar points in rectanglular coordinates » 2006-03-11 12:10:27

lakitu
Replies: 3

My teacher has told me I will need to be able to do these in my up and comping exam later this month. He covered the topic a while ago but I didn't quite understand. Here is an example I have.

Express the polar point (6, 120 °) in rectangular coordinates.

I have no idea how to start doing these? Guidence of any kind would be wonderful.

Regards Lakitu

## #3 Re: Help Me ! » parametric equations as a cartesian equation help » 2006-03-08 05:29:32

thank you to both of you ! big help i understand it all

regards

lakitu

## #4 Re: Help Me ! » parametric equations as a cartesian equation help » 2006-03-08 03:48:52

hi again, i have re written my question in a better way, sorry for the confusion.

i have figured out how to do a simple parametric - cartesian equation in the form of x and y here is what i have already done.

x = 2 t - 2 -----------------(1)
y = 3 t - 2 -----------------(2)

multiply (1) by 3 and (2) by 2.

3x = 6 t - 6 -----------------(3)
2y = 6 t - 4 -----------------(4)

eliminate t from the two eqns by subtracting (4) from (3)

3x - 2y = -6 + 4
3x - 2y = -2

in my exam i am assured i will need to know harder ones like this, but i cannot figure out how to do these.

Express the parametric equations x = t + 1 and y = -3 t² + 3 t as a Cartesian equation in just x and y.

i also need to simpify this in the form y = a x² + b x + c.

Any help would be great.

kind regards lakitu

## #5 Help Me ! » parametric equations as a cartesian equation help » 2006-03-08 03:15:54

lakitu
Replies: 8

hi apologise if this is in the wrong forum

my lecturer has told me that i need to be able to express parametric equations as a cartesian equation and then Simplify it into the form y = a x² + b x + c in my exam later this month. my mind boggles !

here is an example i have found.

Express the parametric equations x = t + 1 and y = -3 t² + 3 t as a Cartesian equation in just x and y.

any help would be great!

kind regards lakitu