First problem: Draw the triangle whose vertices are the points A (1; 3), B (-3; 3) and the intersection point C of the bisector of the second and fourth quadrant with the line x-y-2 = 0. Find the equation for the circumscribed circle of the triangle. (Solution: x ^ 2 + y ^ 2 + 2x-2y-6 = 0) Second problem: Two circles are concentric. One has the equation 4x ^ 2 + 4y ^ 2-6x + 8y-23 = 0, the other passes through P (3/4; -2). Find the equation for the second circle. (Solution: 16x ^ 2 + 16y ^ 2-24x + 32y + 9 = 0)

Determine the equation of the following circle:
(attached photo)