What is the equation of the circle with center at the midpoint of the line segment joining the points (1, 1) and (3, 3) and radius?
1
x2 + y2 − 4(x + y) + 7 = 0
2
x2 + y2 − 4(x + y) + 6 = 0
3
x2 + y2 + 4(x + y)
4
x2 + y2 + 4(x + y) + 8 = 0
5
Not Attempted