Maybe our third subdivision, the right edge, is at x is equal to three. So it would be right over there. And then our fourth subdivision, let's just do it at x equals seven. And we're using the right edge of the subdivisions. Remember, this is a right Riemann sum. So we use the right edge, the value of the function there is just like that. And now you can see for any one of these subdivisions, our rectangles are underestimates of the area under the curve.