Private Sub Worksheet_Change(ByVal Target As Range)
Dim myAdd As String
Dim myVal As Double
Dim mySht As String
Dim myRow As Integer
mySht = "Sheet1" ' Change to suit
myAdd = "$A$10" ' Cell to check; Change to suit
myVal = 20 ' Check for this value; Change to suit
myRow = 10 ' Hide this row; Change to suit
If Target.Address = myAdd And Target.Value = myVal Then
Worksheets(mySht).Rows(myRow).Hidden = True
ElseIf Target.Address = myAdd And Target.Value <> myVal Then
Worksheets(mySht).Rows(myRow).Hidden = False
End If
End Sub