x = 3 cos t,
y = 3 sin t
Square both equations and then add them. You will get
+ = + = = 9.
Thus finally your equation is
= 9. (1)
It is the equation of the circle of the radius 3 units centered at the origin of the coordinate system at (x,y)-coordinate plane.
Thus the parameter " t " is just eliminated, and the result is the equation (1).
Solved, explained and completed.
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By the way, this your post is a duplicate.
It was posted to the forum 3 - 4 days ago, and I and @greenestamps just answered it.
So, I do not understand what was the meaning of posting it again.
