1, the perimeter of the rectangle = (length+width) ×2 C=(a+b)×2.

2. The circumference of a square = side length ×4 C=4a.

3. Area of rectangle = length× width S=ab

4. Square area = side length x side length s = a.a = a.

5. Area of triangle = base × height ÷2 S=ah÷2.

6. parallelogram area = bottom x height S=ah

7. trapezoidal area = (upper bottom+lower bottom) × height ÷ 2s = (a+b) h ÷ 2.

8. Diameter = Radius× 2D = 2r Radius = Diameter ÷2 r= d÷2

9. The circumference of a circle = π× diameter = π× radius× 2c = π d = 2π r.

10, area of circle = π× radius× radius.

1 1, the surface area of a cuboid = (length× width+length× height+width× height )× 2 formula: S=(a×b+a×c+b×c)×2.

12, cuboid volume = length× width× height formula: V = abh.

13, the surface area of the cube = side length× side length× 6 formula: S=6a2.

14, cuboid (or cube) volume = bottom area × height formula: V = abh.

15, volume of cube = side length × side length × side length formula: V = a3.

16. Side surface area of the cylinder: the surface (side surface) area of the cylinder is equal to the perimeter of the bottom multiplied by the height. Formula: s = ch = π DH = 2π RH.

17, the 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.

18, volume of cylinder: the volume of cylinder is equal to the bottom area multiplied by the height. Formula: V=Sh

19, cone volume = 1/3 bottom × product height. Formula: V= 1/3Sh