Learning goals: Teacher Facing Critique whether a given equation represents the relationship between angles in a diagram. Solve an equation that represents a relationship between angle measures, and explain (in writing and using other representations) the reasoning. Write an equation of the form $px+q=r$ or $p(x+q)=r$ to represent the relationship between angles in a given diagram. Full lesson plan (warm-up, activities, synthesis, cool-down prompt) from 7.7 Angles, Triangles, and Prisms, Grade 7.