**Submitting Organization:** Illustrative Mathematics

**Grade Levels: **11th Grade

**Subject Area:** Math

**Standards Alignment: **Common Core State Standards – Math

CCSS.MATH.CONTENT.8.F.B.4 This task connects to high school content standard HAS-REI.B.4 about solving quadratic equations, and to mathematical practice standard MP.7: Look for and make use of structure.

**Description of the Activity: **

The purpose of this task is to help students see structure in algebraic expressions and equations (MP.7). It is one out of a series of three tasks.

**Discussion Questions:**

- (after part (a)) Each function has an n^2 in the expression defining it. Can you see the n^2 in the corresponding pattern?
- (after part (b)) What did you notice about 404 that helped you figure out which pattern had 404 tiles in it? What about 432 and 195?
- What operations did you perform on the numbers in part (b) to figure out the step number?

**Resources Needed:**

None

**Link to further resources:**

https://www.illustrativemathematics.org/content-standards/tasks/2121