X = R * Cos(theta)
    Y = R * Sin(theta)

When the program's Timer fires, the code rotates two Line controls. For the first, it makes the Line's second end point rotate around its first end point.

The program rotates the second Line's end points around the line's center.

Private Const D_THETA = 3.14159265 / 12
Private Theta As Single
Private R1 As Single
Private R2 As Single
Private Cx1 As Single
Private Cy1 As Single
Private Cx2 As Single
Private Cy2 As Single

Private Sub Form_Load()
Dim dx As Single
Dim dy As Single

    dx = Line1.X2 - Line1.X1
    dy = Line1.Y2 - Line1.Y1
    R1 = Sqr(dx * dx + dy * dy)
    Cx1 = Line1.X1
    Cy1 = Line1.Y1

    dx = Line2.X2 - Line2.X1
    dy = Line2.Y2 - Line2.Y1
    R2 = Sqr(dx * dx + dy * dy) / 2
    Cx2 = (Line2.X1 + Line2.X2) / 2
    Cy2 = (Line2.Y1 + Line2.Y2) / 2
End Sub

Private Sub Timer1_Timer()
    Theta = Theta + D_THETA

    Line1.X2 = Cx1 + Cos(Theta) * R1
    Line1.Y2 = Cy1 + Sin(Theta) * R1

    Line2.X1 = Cx2 + Cos(Theta) * R2
    Line2.Y1 = Cy2 + Sin(Theta) * R2
    Line2.X2 = Cx2 - Cos(Theta) * R2
    Line2.Y2 = Cy2 - Sin(Theta) * R2
End Sub