SAT Quadratics Guide: Every Formula and Trick
Quadratics appear on nearly every Digital SAT Math module. Here's every formula, factoring trick, and Desmos shortcut you need.
The Three Forms of a Quadratic
Each form exposes different information about the parabola.
- Standard: y = ax² + bx + c — y-intercept is visible.
- Vertex: y = a(x − h)² + k — vertex is (h, k).
- Factored: y = a(x − r₁)(x − r₂) — roots are r₁ and r₂.
Fastest Way to Find Roots
Graph the quadratic in Desmos. The x-intercepts are the roots. If Desmos isn't practical, factor first; if it doesn't factor cleanly, use the quadratic formula.
Related Posts
- Every SAT Math Formula You Need to Memorize
The complete list of Digital SAT math formulas to memorize — including what the reference sheet already covers and what it doesn't.
- How to Use Desmos on the Digital SAT
A tactical guide to using the built-in Desmos graphing calculator on the Digital SAT Math section — the shortcuts that save the most time.
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