Last-Minute SAT Review: Essential Formulas, Rules & Strategies for Test Day Success
Test day is approaching fast. Whether you have 24 hours or just a few days left, this comprehensive last-minute SAT review consolidates everything you need to maximize your score. The Digital SAT in 2025 features 98 questions across Reading & Writing and Math sections, with adaptive testing that adjusts difficulty based on your performance. This guide covers the most critical math formulas, grammar rules, and test-taking strategies compiled by SAT preparation experts at SATHELP24x7.com.
This review prioritizes high-frequency concepts that appear on nearly every SAT exam. Focus on understanding and applying these essentials rather than trying to learn new concepts from scratch. Remember: confidence and strategy matter just as much as content knowledge.
SAT Math: Essential Formulas You Must Know
The SAT Math section comprises approximately 70% algebra-based questions, with the remaining 30% covering geometry, trigonometry, and data analysis. While the SAT provides a small reference sheet with basic geometry formulas, you must memorize most equations. The Digital SAT allows calculator use throughout both math modules, but mental recall of formulas saves precious time.
Algebra Formulas (35% of Math Section)
- Slope Formula: \( m = \frac{y_2 - y_1}{x_2 - x_1} \)
- Slope-Intercept Form: \( y = mx + b \) where \( m \) is slope and \( b \) is y-intercept
- Point-Slope Form: \( y - y_1 = m(x - x_1) \)
- Standard Form: \( Ax + By = C \)
- Quadratic Formula: \( x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \)
- Discriminant: \( b^2 - 4ac \) (determines number of solutions)
- Vertex Form: \( y = a(x - h)^2 + k \) where \( (h, k) \) is the vertex
- Factored Form: \( y = a(x - r_1)(x - r_2) \) where \( r_1, r_2 \) are roots
- Exponential Growth/Decay: \( y = a(1 \pm r)^t \)
- Compound Interest: \( A = P\left(1 + \frac{r}{n}\right)^{nt} \)
- Simple Interest: \( I = Prt \)
- Distance Formula: \( d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} \)
- Midpoint Formula: \( M = \left(\frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2}\right) \)
- Direct Variation: \( y = kx \)
- Difference of Squares: \( a^2 - b^2 = (a-b)(a+b) \)
Geometry & Trigonometry Formulas (15% of Math Section)
- Pythagorean Theorem: \( a^2 + b^2 = c^2 \)
- Area of Triangle: \( A = \frac{1}{2}bh \)
- Area of Rectangle: \( A = lw \)
- Area of Trapezoid: \( A = \frac{1}{2}(b_1 + b_2)h \)
- Circle Circumference: \( C = 2\pi r \)
- Circle Area: \( A = \pi r^2 \)
- Arc Length: \( L = \frac{\theta}{360°} \times 2\pi r \)
- Sector Area: \( A = \frac{\theta}{360°} \times \pi r^2 \)
- Equation of Circle: \( (x - h)^2 + (y - k)^2 = r^2 \)
- Volume of Cylinder: \( V = \pi r^2 h \)
- Volume of Cone: \( V = \frac{1}{3}\pi r^2 h \)
- Volume of Sphere: \( V = \frac{4}{3}\pi r^3 \)
- Surface Area of Sphere: \( SA = 4\pi r^2 \)
Special Right Triangles
- 45-45-90 Triangle: sides in ratio \( x : x : x\sqrt{2} \)
- 30-60-90 Triangle: sides in ratio \( x : x\sqrt{3} : 2x \)
Trigonometry Essentials
- SOHCAHTOA: \( \sin\theta = \frac{\text{opposite}}{\text{hypotenuse}} \), \( \cos\theta = \frac{\text{adjacent}}{\text{hypotenuse}} \), \( \tan\theta = \frac{\text{opposite}}{\text{adjacent}} \)
- Pythagorean Identity: \( \sin^2\theta + \cos^2\theta = 1 \)
- Complementary Angles: \( \sin(90° - \theta) = \cos\theta \)
Statistics & Probability (15% of Math Section)
- Mean (Average): \( \bar{x} = \frac{\sum x}{n} \)
- Median: Middle value in ordered data set
- Mode: Most frequently occurring value
- Range: Maximum value − Minimum value
- Probability: \( P(E) = \frac{\text{favorable outcomes}}{\text{total outcomes}} \)
- Independent Events: \( P(A \text{ and } B) = P(A) \times P(B) \)
- Expected Value: \( E(X) = \sum (x \cdot P(x)) \)
SAT Reading & Writing: Critical Grammar Rules
The Digital SAT Reading and Writing section tests Standard English conventions through 54 questions across two modules. Grammar accounts for approximately 28 questions. Mastering these core rules helps you identify and correct errors quickly.
Subject-Verb Agreement
Rule: Subjects and verbs must match in number. Singular subjects take singular verbs; plural subjects take plural verbs.
Example: "The team is winning" vs. "The players are winning"
Tricky Case: Compound subjects joined by "and" are plural. Subjects joined by "or" or "nor" match the verb to the nearest subject.
Pronoun-Antecedent Agreement
Rule: Pronouns must match their antecedents in number, gender, and person.
Common Error: "Everyone must bring their ID" → Correct: "Everyone must bring his or her ID"
Key Point: Indefinite pronouns (everyone, anyone, somebody, each, either, neither) are singular.
Modifier Placement
Dangling Modifiers: Ensure the subject being modified appears immediately after the comma.
Wrong: "Walking to school, the rain began to fall."
Correct: "Walking to school, I felt the rain begin to fall."
Misplaced Modifiers: Place modifiers next to the word they describe to avoid ambiguity.
Verb Tense Consistency
Rule: Maintain consistent verb tenses throughout sentences and paragraphs unless time shifts logically.
Wrong: "She studies all night and then slept during the test."
Correct: "She studied all night and then slept during the test."
Punctuation Essentials
Comma Usage: Use commas to separate independent clauses with coordinating conjunctions (FANBOYS: for, and, nor, but, or, yet, so).
Semicolons: Connect two independent clauses without conjunctions or separate complex list items.
Colons: Introduce lists, explanations, or definitions; what follows must complete the sentence.
Dashes: Set off explanatory information or create emphasis.
Sentence Structure
Run-on Sentences: Two independent clauses incorrectly joined without proper punctuation or conjunctions.
Sentence Fragments: Incomplete thoughts lacking either a subject or complete verb.
Parallel Structure: Items in lists or comparisons must maintain the same grammatical form.
Last-Minute Test-Taking Strategies
Time Management Tactics
- Reading & Writing: Spend approximately 1 minute per question. Each module is 32 minutes for 27 questions. Don't get stuck on any single question for more than 90 seconds.
- Math Module 1: 35 minutes for 22 questions (approximately 1.5 minutes per question). Budget extra time for word problems and multi-step equations.
- Math Module 2: Adaptive difficulty means questions become harder or easier based on Module 1 performance. Stay focused regardless of perceived difficulty.
- Skip and Return: Mark difficult questions and return to them if time permits. The Digital SAT allows navigation within each module.
Process of Elimination
- Answer Every Question: No penalty for wrong answers means you should never leave questions blank. Eliminate obviously wrong choices and make educated guesses.
- Math Shortcuts: Plug answer choices back into equations when solving seems complex. Work backwards from answers, especially on multiple-choice algebra problems.
- Grammar Elimination: Cross out answers that violate basic rules (subject-verb agreement, pronoun errors, etc.) before considering style and conciseness.
Reading Comprehension Efficiency
- Read Questions First: Skim the question before reading the passage to know what to look for. This targets your reading and saves time.
- Focus on Main Ideas: Don't get bogged down in details. Identify the author's purpose, tone, and central argument. Many questions test comprehension of overall meaning.
- Evidence-Based Answers: Every correct answer has textual support. If you can't point to evidence in the passage, reconsider your choice.
Calculator Strategy
- Use Desmos Wisely: The built-in Desmos calculator can graph equations, solve systems, and perform statistical calculations. Familiarize yourself with its functions before test day.
- Mental Math First: Don't rely on the calculator for simple arithmetic. Mental calculation is faster for basic operations and reduces input errors.
- Check Your Work: Use the calculator to verify complex calculations, but don't let it slow you down on straightforward problems.
The Night Before: What to Do (and What NOT to Do)
DO: Review formula flashcards one final time. Organize your test materials (ID, admission ticket, calculator if allowed, snacks). Get 7-8 hours of sleep. Eat a nutritious dinner and prepare a protein-rich breakfast.
DON'T: Attempt to learn completely new concepts. Stay up late cramming (sleep is more valuable). Consume excessive caffeine that might cause jitters. Stress about perfection—focus on doing your personal best.
Test Day Morning Checklist
- Arrive Early: Plan to reach the test center 30 minutes before check-in. Late arrivals risk not being admitted.
- Bring Required Items: Valid photo ID, admission ticket, approved calculator (if taking paper SAT), #2 pencils (paper test), and permitted snacks.
- Eat Strategically: Choose a breakfast with protein and complex carbohydrates that provides sustained energy. Avoid sugary foods that cause energy crashes.
- Stay Calm: Practice deep breathing if you feel anxious. Remind yourself that you're prepared and capable. Confidence improves performance.
Adaptive Testing: Understanding the Digital SAT Format
The 2025 Digital SAT uses adaptive testing technology, meaning your performance on the first module determines the difficulty of the second module. Here's what you need to know:
- Two-Stage Adaptive: Each section (Reading & Writing, Math) contains two modules. Module 2 difficulty adjusts based on Module 1 results.
- Don't Panic if Module 2 Feels Harder: A more difficult second module indicates strong first-module performance—this is good news for your score.
- Easier Module 2 Doesn't Mean Failure: Your score depends on both accuracy and question difficulty. Focus on answering questions correctly regardless of perceived difficulty.
- Stay Consistent: Maintain effort and focus throughout both modules. Every correct answer contributes to your final score.
Need More Practice?
Visit SATHELP24x7.com for full-length practice tests, personalized study plans, and expert tutoring. Our proven strategies have helped thousands of students achieve their target scores.
You've got this! Trust your preparation, stay focused, and approach each question methodically. Good luck on test day!
Final Words of Encouragement
Last-minute review is about reinforcing what you already know, not learning everything from scratch. Focus on your strengths while quickly reviewing areas of weakness. The SAT tests your ability to think critically and apply knowledge under time pressure—skills you've been developing throughout your education.
Remember that the SAT is just one component of your college application. While a strong score opens doors, it doesn't define your worth or potential. Approach the test with confidence, maintain a positive mindset, and trust in the preparation you've done.
Stay calm, breathe deeply, and tackle one question at a time. You're capable of achieving your goals. Now go show that SAT what you're made of!