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waheguru
The lenght from the center of teh circle to a point on the circle is r = square root of 40 what is the length of the radius the answer is 2 and squareroot 10?
\[ \sqrt{40} = \sqrt{4}\times\sqrt{10}=2\sqrt{10} \]
but the first number has to be a perfec square right?
You can pull out any perfect squares.
Since \(40=2\cdot 2\cdot 2\cdot 5\) you can pull out the \(2\cdot 2\), and he \(2\cdot 5\) remains inside.