The equation of a circle which has a center at $(-5,2)$ can be written as $Ax^2 + 2y^2 + Bx + Cy = 40.$ Find the radius of the circle.

\((x+5)^2+(y-2)^2 = r^2\\ x^2 + 10x + 25 + y^2 - 2y+4 = r^2\\ x^2 + 10x + y^2 -2y = r^2 -29\\ 2x^2 + 20x +2y^2 - 4y = 2r^2 - 58 = 40\\ 2r^2 = 98\\ r^2 = 49\\ r = 7\)

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