Common Core State Standard: 8.NS.A.2
Domain: The Number System
Theme: Know that there are numbers that are not rational, and approximate them by rational numbers
Standard Description: Use rational approximations of irrational numbers to compare the size of irrational numbers, locate them approximately on a number line diagram, and estimate the value of expressions (e.g., ?^2). For example, by truncating the decimal expansion of ?2 (square root of 2), show that ?2 is between 1 and 2, then between 1.4 and 1.5, and explain how to continue on to get better approximations.