Learning goals: Teacher Facing Evaluate an expression for given values of the variable, including negative values, and compare (orally) the resulting values of the expression. Generalize (orally) about the relationship between additive inverses and about the relationship between multiplicative inverses. Identify numerical expressions that are equal, and justify (orally) that they are equal. Full lesson plan (warm-up, activities, synthesis, cool-down prompt) from 7.5 Rational Number Arithmetic, Grade 7.