SAT Math Guides
Straight, accurate answers to how the Digital SAT Math section actually works — written by Lighthouse Math (灯塔数学), a diagnostic-driven SAT tutoring program.
How Digital SAT Math Module 2 Adaptive Difficulty Works
The Digital SAT Math is section-adaptive: your Module 1 accuracy routes you to a harder or easier Module 2 that caps or unlocks your score. Here's the mechanism and what to do about it.
SAT Math Grid-In Rules: Fractions, Decimals & Multiple Answers
Digital SAT student-produced response (grid-in) rules: negatives are allowed, no mixed numbers, don't round too early, and how to enter fractions vs. repeating decimals correctly.
Desmos Graphing Calculator Strategies for Digital SAT Math
The Digital SAT ships a built-in Desmos calculator for the whole Math section. Use it to solve equations by intersection, find roots, run regressions, and check answers — plus when NOT to.
SAT Math Score Bands: What 600 vs 700 vs 750 Requires
What separates a 600, 700, and 750 on Digital SAT Math — the module routing, the error tolerance out of ~44 questions, and the specific skills each band demands across the four content domains.
SAT Math Quadratics: Vertex, Factoring & the Discriminant
The three quadratic forms on the SAT — standard, factored, and vertex — plus how the discriminant tells you the number of real solutions, and when to just graph in Desmos.
SAT Math Linear Systems: Substitution, Elimination & Word Problems
How to solve SAT linear systems by substitution and elimination, how to spot no-solution and infinite-solution systems from the coefficients, and a repeatable way to translate word problems.
SAT Math Exponential Growth & Decay: Percent Change, Half-Life
How to read and build SAT exponential models: the y = a·bˣ form, turning a percent increase or decrease into the base b, half-life and doubling, and linear vs. exponential growth.
SAT Math Geometry: Circles, Triangles & Coordinate Geometry
The SAT geometry essentials: the circle equation and arc/sector rules, special right triangles and similarity, and coordinate-geometry distance, midpoint, and slope — with what is (and isn't) on the reference sheet.