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A circle whose center is at C(x=-4,y=1) passes through the point D(x=-2,y=2). Find the length of the radius.
You may enter a number, an expression such as 'sqrt()', or an algebraic statement such as '1/sqrt(3**2 + 4^2)', where we have explicitly shown that either '**' or '^' may be used as a power.

radius =
Query, is the above answer correct?