What is the most logical next event?

How to determine a square and circle of equal area
Let r1 ^ 2 represent the area of the square, a (s).
Let r2 ^ 2 = the area of the circle, a (c).
Set a (s) = a (c) via r1 ^ 2 = r2 ^ 2.

Available options:
[I] ( write the area of the square in question before its relative value instead of the area (this is provided with the radius formula). For the circle, you can simply write the area of the square and multiply by 1 for the radius of the circle.
[II] Then r1 ^ 2/r2 ^ 2 = and r1/r2 = sqrt (). Given either r1 or r2, we can determine the other one.
[III] Put the r2 ^ 2 + r2 together to form a circle the size of the square. Put quadractopple/sr2[r1].
[IV] Bring the whole square and circle into a grid where it's equal. Note that the diagonals of a grid are the same (( (1/s) )) ) as those of the squares.
[II]