Geometry Flashcards

1
Q

Area of a triangle

A

(B x H) / 2 = Area

2
Q

Area of a rectangle

A

L x H = Area

3
Q

Area of a trapezoid

A

((Base1 + Base2) / 2) x H = Area

4
Q

Area of a parallelogram

A

B x H = Area

5
Q

Area of a rhombus

A

(Diagonal x Diagonal) / 2 = Area

6
Q

Volume of a rectangular solid

A

L x W x H = Area

7
Q

Formula for sum of interior angles of a polygon

A

(n - 2) * 180

8
Q

Three common types of right triangles

A

1) 3 - 4 - 5 (6,8,9) (9,12,15) (12,16,20)
2) 5 - 12 - 13 (10,24,26)
3) 8 - 15 - 17

9
Q

Ratio of sides for isosceles triangles

A

45 - 45 - 90
1 : 1 : √2
x : x : √x

10
Q

Ratio of sides for equilateral triangles

A

30 - 60 - 90
1 : √3 : 2
x : x√3 : 2x

11
Q

Formula for diagonal of a square

A

d = s√2

12
Q

Formula for diagonal of a cube

A

d = s√3

13
Q

Ratio of similar triangle side lengths to area ratios

A

Length - a : b

Area - a² : b²

14
Q

Formula for area of an equilateral triangle

A

(S²√3) / 4 = Area

15
Q

Circumference of a circle

A

C = 2πr or C = dπ

16
Q

Area of a circle

A

A = πr²

17
Q

Surface area of a cylinder

A
```SA = 2 circles + rectangle
SA = 2(πr²) + 2πrh```
18
Q

Volume of a cylinder

A

V = πr²h