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# Connected

## Do social networks make us more connected?

In 2004, Facebook launched to little fanfare. Today, approximately 25% of the world’s population uses it every month, and Facebook describes its mission as to create a "global community for bringing people together."

In this lesson, students write a quadratic function to model the number of possible connections between users on a social network. They use information about how Facebook has grown over time to determine how the number of connections has changed, and discuss whether this technology is expanding our perspectives or reinforcing those we already have.

### REAL WORLD TAKEAWAYS

• As a social network grows, the number of possible connections among users grows by more and more.
• Because Facebook users interact with a fraction of other users, not all of these possible connections are realized.
• Facebook allows us to connect with new ideas; it also allows us to disconnect from ideas we don’t agree with.

### MATH OBJECTIVES

• Given a pattern, create a rule to determine the next value in the sequence.
• Write and graph a quadratic function to model a real-world scenario; interpret the meaning of a non-linear rate of change
• Evaluate a quadratic function for different values of x.

Appropriate most times as students are developing conceptual understanding.
Algebra 1