



 
Hi Geraldine, A square with area 25 cm squared = 5^{2} cm squared has sides of length 5 cm. There are 4 sides so the wire is of length 4 × 5 = 20 cm. If the wire is cut and then bent into two identical circles the wire must be cut in half. Thus half the wire length is the circumference of one of the circles. What is the formula for the circumference of a circle? In this formula you know the circumference and hence you can solve for the radius. I hope this helps,  


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