### Home > AC > Chapter 12 > Lesson 12.4.2 > Problem 12-80

12-80.

If a tile pattern can be described by the equation , where

*represents the figure number and*

*represents the number of tiles, find each of the following.*

The number of tiles in Figure 211.

The number of the figure that contains

tiles.

Substitute .

Substitute .

Set the equation equal to zero.

Factor the expression.

or

The figure number cannot be negative.

Figure