Learning goals: Teacher Facing Explain (in writing) the steps used to derive the quadratic formula. Explain (orally and in writing) how the solutions obtained by completing the square are expressed by the quadratic formula. Understand that the quadratic formula can be derived by generalizing the process of completing the square. Full lesson plan (warm-up, activities, synthesis, cool-down prompt) from Alg1.7 Quadratic Equations, Algebra 1.