Top 15 Formulas You Must Know for SAT Math

You do not need to memorize every formula in your textbook to score well on SAT Math — but you do need to know the right ones. The test leans on a core set of formulas that appear again and again across algebra, geometry, and data analysis questions.

The Digital SAT (2024 format) is scored 400–1600. The Math section runs about 70 minutes and you have access to Desmos for every question — which means computation is less of a barrier, but knowing which formula to use is still everything.

Core Algebra Formulas

These show up constantly. Have them automatic:

• Slope: m = (y₂ − y₁) / (x₂ − x₁)
• Slope-intercept form: y = mx + b
• Point-slope form: y − y₁ = m(x − x₁)
• Quadratic formula: x = [−b ± √(b² − 4ac)] / (2a)
• Exponent rules: aᵐ × aⁿ = aᵐ⁺ⁿ and (aᵐ)ⁿ = aᵐⁿ

For systems of equations, remember: substitution works best when one variable is already isolated. Elimination works best when coefficients are easy to match.

Geometry Formulas

The SAT provides a reference sheet, but you want these automatic so you don't waste time flipping back to it:

• Area of rectangle: A = lw
• Area of triangle: A = ½ × base × height
• Pythagorean theorem: a² + b² = c²
• Circle circumference: C = 2πr
• Circle area: A = πr²
• Volume of rectangular prism: V = lwh

Memorize common Pythagorean triples: 3-4-5, 5-12-13, and their multiples. They show up more often than you'd expect.

Statistics and Percent Formulas

These come up in nearly every SAT Math section:

• Mean: sum ÷ count
• Distance formula: d = √[(x₂−x₁)² + (y₂−y₁)²]
• Midpoint: ((x₁+x₂)/2, (y₁+y₂)/2)
• Percent change: (new − old) / old × 100
• Exponential growth: final = initial × (1 ± r)ᵗ

For percent questions, always identify what the "original" is before dividing. Students frequently use the wrong denominator and lose easy points.

How to Study SAT Math Formulas

Passive review isn't enough. To really lock formulas in:

1. Write each formula by hand several times a week
2. Create flashcards — formula on one side, a sample problem on the other
3. Do targeted practice problems that use that specific formula
4. Review your formula sheet for 5–10 minutes before every study session

The goal is recognizing which formula fits a question under time pressure — not just knowing the formula exists. That recognition comes from doing problems, not just reading notes.

Using Desmos Strategically

Since Desmos is available for all SAT Math questions in the digital format, use it to verify — not replace — your algebra. For quadratic questions, graph the equation to check your roots. For linear systems, graph both lines to find the intersection. Desmos is fastest for visual confirmation, not for solving from scratch.

Ready to sharpen your SAT Math formula skills? SimpUTech's SAT Math AI Study Coach gives you adaptive practice that targets the exact formula types you keep missing. Start your free 3-day trial at simputech.com.