### Home > CALC > Chapter 1 > Lesson 1.3.1 > Problem 1-109

1-109.

Which graph is the closest to the exact area under the curve?

Midpoint Rectangles

Notice that the graphs in the diagrams above show an increasing function. That is, as *x* increases, the *y*-values increase. What if we graphed a decreasing function instead? Would left-endpoint rectangles be underestimates then?