Eliminate the parameter and write the corresponding rectangular equation whose graph represents the curve.

x = sqrt t
y = 1 - t

2 answers

from first:
x = √t
so x^2 = t

from the second
t = 1-y

so x^2 = 1 - y
or
y = 1 - x^2 , a parabola
A polygon with 4 sides no two of wich need to be the same size