The ACT gives you no formula sheet, so you'll want to memorize key formulas for area and volume, the slope and distance formulas, the quadratic formula, and basic trig ratios. Knowing them cold saves time and keeps easy points from slipping away.
Geometry formulas
Memorize area of triangles, rectangles, circles, and trapezoids; circumference; and volumes of boxes, cylinders, and spheres. The Pythagorean theorem and special right triangles (30-60-90, 45-45-90) appear often. See how much geometry is on the ACT.
Coordinate geometry
Know slope (rise over run), the slope-intercept form y = mx + b, the midpoint formula, and the distance formula. Many coordinate questions become quick points once these are automatic.
Algebra formulas
The quadratic formula, factoring patterns, exponent rules, and the equation of a line are essential. These power the largest share of the test; see how much algebra is on the ACT.
Trigonometry
SOHCAHTOA for sine, cosine, and tangent, plus the basic identities. A few questions each test reward knowing these without hesitation.
Statistics
Mean, median, mode, range, and basic probability (favorable over total). Simple, but worth memorizing so you never stall on a definition.
Turn formulas into instinct
Flashcards get you to recognition; timed practice gets you to instant recall. Drill formula-based questions on thirty-six until you apply them without thinking, then build the rest of your plan with how to improve your ACT Math score.
Start practicing
Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.
This article offers general ACT prep guidance. The ACT can change from year to year, including its format, scoring, policies, test dates, and fees, so always confirm the latest details on the official ACT website at act.org before you make decisions. ACT® is a registered trademark of ACT, Inc. thirty-six is not affiliated with, endorsed by, or sponsored by ACT.