In Step 2, Lara did not ensure that the second diamter was perpendicualr to the first diameter she drew.
The correct steps should be:
Step 1: Use the straightedge to draw a diameter of the circle. Label the points at which the diameter touches the circle as A and B.
Step 2: Draw a second diameter <em>perpendicular to the first diameter</em>. Label the points at which the second diameter touches the circle as C and D.
Step 3: Join the end points of the two diameters to form a square.
The formula for this is

. Filling in accordingly,

. This simplifies to

and 36=6x. Therefore, x = 6 so the bases are 6 and 12.
X would equal 2.7 //////////////