Must-know ACT math formulas?

Hey everyone, I'm preparing for the ACT and was wondering if any of you can suggest essential math formulas that I need to know for the test. Thanks in advance!

Hey there! Preparing for the ACT math section can seem daunting, but having a list of important formulas at hand can definitely help. Here are some essential formulas and concepts you should know for the ACT math section:

1. Slope-intercept form of a linear equation: y = mx + b, where m is the slope, and b is the y-intercept.

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

3. Pythagorean theorem: a² + b² = c², for right-angled triangles.

4. Quadratic formula: x = (-b ± √(b² - 4ac)) / 2a, for ax² + bx + c = 0.

5. Area of a rectangle: A = length × width

6. Area of a triangle: A = ½(base × height)

7. Area of a circle: A = πr²

8. Circumference of a circle: C = 2πr

9. Volume of a rectangular prism: V = length × width × height

10. Volume of a cylinder: V = πr²h

11. Volume of a sphere: V = (4/3)πr³

12. Volume of a cone: V = (1/3)πr²h

13. Trigonometric ratios: sinθ = opposite/hypotenuse, cosθ = adjacent/hypotenuse, tanθ = opposite/adjacent

14. Trigonometric identities: sin²θ + cos²θ = 1, 1 + tan²θ = sec²θ

15. Law of Sines: (sinA/a) = (sinB/b) = (sinC/c)

16. Law of Cosines: c² = a² +b² − 2abcosC

17. Probability: P(A) = number of favorable outcomes / total number of possible outcomes.

18. Arithmetic sequence: an = a1 + (n-1)d, where an represents the nth term, a1 is the first term, n is the number of terms, and d is the common difference.

19. Geometric sequence: an = a1 × r^(n-1), where an is the nth term, a1 is the first term, n is the number of terms, and r is the common ratio.

20. Sum of the angles in a polygon: (n-2) × 180°, where n is the number of sides.

These formulas and concepts cover a variety of topics on the ACT math test. Be sure to practice using these formulas in different problem scenarios to familiarize yourself with how to apply them. Good luck with your preparation!