The formulas you might need for an 8th-grade math test could include:
1. Area of a rectangle: \( A = l \times w \)
2. Area of a triangle: \( A = \frac{1}{2} \times b \times h \)
3. Area of a circle: \( A = \pi r^2 \)
4. Perimeter of a rectangle: \( P = 2l + 2w \)
5. Perimeter of a triangle: \( P = a + b + c \)
6. Circumference of a circle: \( C = 2 \pi r \)
7. Volume of a rectangular prism: \( V = l \times w \times h \)
8. Volume of a cylinder: \( V = \pi r^2 \times h \)
9. Pythagorean theorem: \( a^2 + b^2 = c^2 \) (for right triangles)
10. Slope formula: \( m = \frac{y_2 - y_1}{x_2 - x_1} \)
These should cover many topics in 8th-grade math, but make sure to review your specific curriculum to be fully prepared.
