1. Use the distance formula: d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}
2. Substitute given points: A(5,1) and B(-3,-3)
3. Calculate differences: (-3 - 5)^2 = (-8)^2 = 64 and (-3 - 1)^2 = (-4)^2 = 16
4. Sum the squares: 64 + 16 = 80
5. Take square root: \sqrt{80} = 4\sqrt{5}
6. Therefore, the distance is: 4\sqrt{5}