Find the area of the region enclosed by the graph of x^2 + y^2 = 2x - 6y + 6 + 4x - 8y.
Find the area of the region enclosed by the graph of x^2 + y^2 = 2x - 6y + 6 + 4x - 8y.
x2 + y2 = 2x – 6y + 6 + 4x – 8y
rearrange & group (x2 – 6x ) + (y2 + 14y ) = 6
Complete the squares on x and y. Add the same amount to the right side that you add to the left.
(x2 – 6x + 9) + (y2 + 14y + 49) = 6 + 9 + 49
(x – 3)2 + (y + 7)2 = 64
That's a circle in the form (x – h)2 + (y –k)2 = r2 where h and k locate the center and r is the radius.
Area of the circle is A = π r2 ——>> A = 64 π = 201.06
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