Important ACT Math Formulas to Know

Hey guys! I'm prepping for the ACT and I'm trying to get a solid grasp on the math section. What are some important formulas and equations I should definitely know for the ACT Math? Any advice would be super helpful! Thanks!

Hello! It's great that you're focusing on the math section of the ACT. Knowing important formulas and equations is definitely going to help you tackle diverse problems that might come up in the exam. Here's a list of some key formulas and concepts you should be familiar with for the ACT Math section:

1. Arithmetic and Geometric Sequences:

- Arithmetic: An = A1 + (n-1)d

- Geometric: An = A1 r^(n-1)

2. Quadratic Formula (to solve quadratic equations): x = (-b ± √(b^2 - 4ac)) / 2a

3. Distance Formula: d = √((x2 - x1)^2 + (y2 - y1)^2)

4. Midpoint Formula: M = ((x1 + x2)/2, (y1 + y2)/2)

5. Slope-Intercept Form of a Line: y = mx + b

6. Slope Formula: m = (y2 - y1) / (x2 - x1)

7. Pythagorean Theorem (right triangles): a^2 + b^2 = c^2

8. Trigonometry Ratios (for right triangles):

- Sine (sin): Opposite / Hypotenuse

- Cosine (cos): Adjacent / Hypotenuse

- Tangent (tan): Opposite / Adjacent

9. Circle Formulas:

- Circumference: C = 2πr or C = πd

- Area: A = πr^2

10. Triangle Formulas:

- Area of a triangle: A = 0.5bh (where b is base and h is height)

- Special right triangles: 45-45-90 and 30-60-90

11. Volume of 3D shapes:

- Rectangular Prism: V = lwh

- Cylinder: V = πr^2h

- Sphere: V = 4/3πr^3

- Pyramid: V = 1/3Bh (where B is the base area and h is the height)

These are some of the most important concepts and formulas you'll need to know for the ACT Math section, but it's also crucial to practice your problem-solving skills and be comfortable applying these ideas to various types of problems. The more practice you get, the more confident and prepared you'll be for the exam. Good luck!