Answer:
The center of the circle is (6 , 3)
Explanation:
∵ The vertices of Δ EFG are E (4 , 4) , F (4 , 2) , G (8 , 2)
∵ The x-coordinates of E and E are equal ∴ EF is vertical
∵ The y-coordinates of F and G are equal ∴ FG is horizontal
∴ m∠EFG = 90°
∵ The circle is circumscribed about Δ EFG
∴ E , F , G lie on the circle
∵ m∠F = 90°
∴ EG is the diameter of the circle
∴ The center of the circle is the mid-point of EG
∵ The mid-point of EG is

∴ The center of the circle is (6 , 3)