The diagram represents the area of a rectangle as 9x2 + 24x + 16 square units.

A 2-column table with 2 rows. The labels for the columns and rows are question mark. First column entries are 9 x squared, 12 x. Second column entries are 12 x, 16.
What are the length and width of the rectangle in terms of x?

both: 3x + 4 units
both: 3x + 8 units
width: 3x + 4 units; length: 6x + 12 units
width: 3x + 8 units; length: 6x + 8 units