Private Sub Command1_ Click()
Dim x (10) As Double
Dim y (10) As Double
x(1) = -5.0 : y(1) = 1.0

　　　　省略

x(10) = 4.0 : y(10) = 12.0
Wa = 0
For i = 1 To 10
d = {(2*n + 2 - m) / m }^2
Wa = Wa + d
n = xi
m = yi
Next i
Picture 1. Print Wa
End Sub

a,b がそれぞれ2の場合のやつです。