You can use blocks to build pyramids such as these. All of the pyramids are solid with no empty space inside.
a. Create a table to record the number of layers, x, in each pyramid and the total number of blocks, y, needed to build it. You may need to build or sketch a few more pyramids, or look for patterns in the table.

b. Use finite differences to find a polynomial function that models these data.
c. Find the number of blocks needed to build a pyramid with eight layers.
d. Find the number of layers in a pyramid built with 650 blocks.