Mathematics with applications in the management, Natural, and Social Sciences Twelfth edition

Chapter 6: Systems of Linear Equations and Matrices

6.1 Exercises

23.) According to Google Trends, popular interest in LED lightbulbs has been soaring. while interest in CFLs has been dropping. The following equations approximate the Google Trends rating (on a scale from 0-100) in year x, where x = 10 corresponds to the year 2010. ( Data from www.google.com/trends.)

LED: -25x + 6y = 20

CFL: 15x + 2y = 322

When did interest in ED lighting Surpass CFL lighting? Round your answer to the nearest year.