how to write result with label.text

I'm trying to add 2 numbers and then show the result.

• BUT NOT with Response.Write(result); as I can't place it where I want.

I have this in my aspx:

<asp:TextBox label="tal1" ID="TextBox_Tal1" runat="server"></asp:TextBox>
<asp:TextBox label="tal2" ID="TextBox_Tal2" runat="server"></asp:TextBox>
<asp:Button ID="Button_plus" runat="server" Text="+" OnClick="Button_plus_Click" />
<asp:Label ID="Label_plus" runat="server" Text=""></asp:Label>

And this in my .cs:

public int plus(int tal1, int tal2)
{
    int result = tal1 + tal2;
    return result;
}    

protected void Button_plus_Click(object sender, EventArgs e)
{
    int tal1 = Convert.ToInt32(TextBox_Tal1.Text);
    int tal2 = Convert.ToInt32(TextBox_Tal2.Text);
    plus(tal1, tal2);        
}