### 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.

Substitute

into the equation for .The number of the figure that contains

tiles. Substitute

into the equation for .Set the equation equal to zero.

Factor the expression.

orThe figure number cannot be negative.

Figure