A New Path to Solving Quadratics

Eighth-grade algebra students continued their exploration of quadratic equations with a recent lesson grounded in curiosity and discovery. They were presented with two equations:

x² + 4x + 1 = 0
(x + 2)² = 3

After solving both, students noticed something surprising: each equation led to the same solution. This prompted a class discussion about efficiency: which equation was easier to solve, and why? Students quickly recognized that the second equation was both faster and more straightforward, sparking interest in how more complex equations could be transformed into this simpler form.

That question led to the introduction of a new method: completing the square.

To build understanding, students began by working with algebra tiles on equation mats, physically arranging pieces to form perfect squares. This hands-on approach helped them see how a trinomial in standard form could be reorganized into a squared expression—and what adjustments were needed to make that transformation possible.

With practice, students transitioned from concrete models to abstract reasoning. As a class, they discussed how to generalize the process and apply it without tiles. They even developed their own formula for completing the square, deepening their conceptual understanding.

Through exploration, collaboration, and reasoning, Saklan’s eighth graders didn’t just learn a new method; they discovered it. This kind of learning empowers students to approach complex problems with confidence, creativity, and a strong sense of mathematical thinking.

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Author: The Saklan School Friday Blog

The Saklan School is a private Pre-K through 8 school located in Moraga, CA. Our mission is to think creatively, act compassionately, and live courageously.