Codigo:
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Dim rowNumberValue As Integer, F As Integer
Dim columnNumberValue As Integer, C As Integer
Cells.Interior.ColorIndex = 0
rowNumberValue = ActiveCell.Row
columnNumberValue = ActiveCell.Column
For F = 1 To rowNumberValue
Cells(F, columnNumberValue).Interior.ColorIndex = 36
Next F
For C = 1 To columnNumberValue
Cells(rowNumberValue, C).Interior.ColorIndex = 36
Next C
End Sub