7.NOS.A.1: Add and subtract rational numbers using multiple strategies and representations. a. Describe situations in which opposite quantities combine to make 0. b. Model the addition of rational numbers as movement along a number line, where the direction and distance depend on the sign and magnitude of the addend. Show that a number and its opposite have a sum of 0 (are additive inverses). c. Rewrite subtraction as addition using the additive inverse p – q = p + (–q). Use strategies such as number lines and applying absolute value of the difference to determine the distance between two rational numbers and solve problems in context. d. Model and solve multistep contextual problems involving addition and subtraction of rational numbers, using efficient and flexible strategies.