Excel VBA How to draw a line in a graph

Question

Please view this image to get my clearly question: 

Answer 1

Sub MakeChart()

    Dim x(20) As Variant
    Dim y(20) As Variant
    Dim i     As Long
    
    For i = 0 To 20
        x(i) = i * 2
        y(i) = 2 * Sin(i / 5)
    Next
 
    Charts.Add
    
    With ActiveChart
        .ChartType = xlLineMarkers
        .HasTitle = True
        .ChartTitle.Text = "Plot from Array"
        
        With .Axes(xlCategory, xlPrimary)
            .HasTitle = True
            .AxisTitle.Characters.Text = "X"
        End With
        
        .SeriesCollection.NewSeries
        With .SeriesCollection(1)
            .XValues = x
            .Values = y
            .Trendlines.Add
            .Trendlines(1).DisplayEquation = True
            .Name = "Y"
        End With
    
    End With
    
End Sub

That draws a curve then fits a trend line to it.

If you replace the loop at the start of the code that populates the arrays with your code to get the data it should do what you want.