Formulas to remember for the ACT

Hey everyone! I was wondering if anybody has a list of essential math formulas that I should remember for the ACT? I'm a bit stressed out about it, and I want to be as prepared as possible. Thanks!

Hi! Prepping for the ACT math section can certainly feel overwhelming, but I'm glad you're asking for help and focusing on important formulas. Here's a list of some essential math formulas that you should remember for the ACT:

1. Slope-intercept form: y = mx + b

2. Point-slope form: y - y1 = m(x - x1)

3. Quadratic formula: x = [-b ± √(b² - 4ac)] / 2a

4. Pythagorean theorem: a² + b² = c²

5. Distance formula: d = √[(x₂ - x₁)² + (y₂ - y₁)²]

6. Midpoint formula: M(x, y) = [(x₁ + x₂)/2, (y₁ + y₂)/2]

7. Area of a rectangle: A = lw (length x width)

8. Area of a triangle: A = (1/2)bh (base x height)

9. Area of a circle: A = πr²

10. Circumference of a circle: C = 2πr

11. Volume of a rectangular prism: V = lwh (length x width x height)

12. Volume of a cylinder: V = πr²h

13. Sine (SOH): sin(θ) = opposite/hypotenuse

14. Cosine (CAH): cos(θ) = adjacent/hypotenuse

15. Tangent (TOA): tan(θ) = opposite/adjacent

16. Regular polygon sum of interior angles = (n - 2) 180°

17. Exterior angles of a polygon: sum to 360°

18. Probability: P(success) = number of successful outcomes / total number of outcomes

Remember that most of the formulas you need can be derived from basic principles. Be sure to also practice word problems and understanding how to apply these formulas to ACT questions. Good luck with your preparation, and don't forget to do some timed practice tests to get a feel for the pacing!