In Grade 8, instructional time should focus on three critical areas: (1) formulating and reasoning about expressions and equations, including modeling an association in bivariate data with a linear equation, and solving linear equations and systems of linear equations; (2) grasping the concept of a function and using functions to describe quantitative relationships; (3) analyzing two- and three-dimensional space and figures using distance, angles, similarity, and congruence, and understanding and applying the Pythagorean Theorem (Utah Core State Standards for Middle School Mathematics Courses, page 31).