1. Area of triangle = base * height ÷2.
The formula S=a*h÷2.
2. Square area = side length * side length.
Long formula s = a * a
3. Rectangular area = length * width.
The formula s = a * b.
4. The area of parallelogram = bottom * height.
The formula s = a * h.
5. Trapezoidal area = (upper bottom+lower bottom) * height ÷2.
The formula S=(a+b)h÷2.
6. Sum of internal angles: sum of internal angles of triangle = 180 degrees.
7. cuboid volume = length * width * height.
Formula: V=abh.
8. cuboid (or cube) volume = bottom area * height.
Formula: V=abh.
9. The volume of the cube = side length * side length * side length.
Formula: V=aaa.
10. circumference = diameter * π.
Formula: l = π d = 2π r.
1 1. Area of circle = radius * radius * π.
Formula: S=πr2.
12. Surface (side) area of the cylinder: the surface (side) area of the cylinder is equal to the perimeter of the bottom multiplied by the height.
Formula: S=ch=πdh=2πrh.
13. Surface area of the cylinder: the surface area of the cylinder is equal to the perimeter of the bottom multiplied by the height plus the area of the circles at both ends.
Formula: S=ch+2s=ch+2πr2.
14. Volume of the cylinder: the volume of the cylinder is equal to the bottom area multiplied by the height.
Formula: V=Sh.
15. Cone volume = 1/3 * product bottom height.
Formula: V= 1/3Sh.