Circumference of a circle = pi(Diameter)
Circumference of a circle = 2(pi)(Radius)
Area of a circle = pi(Radius)2

Cone Volume = pi(Base Area)(Height)
Cone Volume = .33(pi)(Radius of Base)(Height)

Cube Diagonal Length = Side (SquareRt(3))
Cube Surface Area = 6(Side)(Side)
Cube Volume = (Side)(Side)(Side)

Cylinder Lateral Area = 2(pi)(Radius)(Height)
Cylinder Total Area = (2(pi)(Radius)(Height)) + (2pi(Radius)(Radius))
Cylinder Volume = (Base Area)(Height)
Cylinder Volume = pi(Height)(Radius)(Radius)

Distance in a Plane = SquareRt[(x2 - x1)(x2 -x1)+ (y2 - y1)(y2 - y1)]
Distance in Three Dimensions = SquareRt[(x2 - x1)(x2 - x1) + (y2 - y1)(y2 - y1) + (z2 - z1) (z2 - z1)]

Area of a Parallelogram = (Base)(Height)

Volume of a Rectangular Prism = (Base Area)(Height)

Volume of a Pyramid = .33(Base Area)(Height)

Perimeter of a Rectangle = 2(Length) + 2(Width)
Area of a Rectangle = (Length)(Width)

Diagonal Length of a Rectangular Solid = SquareRt[(Length)(Length) + (Width)(Width) + (Height)(Height)]
Area of a Rectangular Solid = 2(Length)(Width) + 2(Width)(Height) + 2(Length)(Height)
Volume of a Rectangular Solid = (Length)(Width)(Height)

Perimeter of an n-sided polygon = n(Length of a side)

Area of a sphere = 4pi((Radius)(Radius))
Volume of a sphere = (4pi((Radius)(Radius)(Radius)))/3

Diagonal of a Square = (Side)SquareRt(2)
Perimeter of a Square = 4(Side)
Area of a Square = (Side)(Side)

Area of a Trapezoid = ½(Height)(b1 + b2)
Perimeter of a Triangle = (Side A) + (Side B) + (Side C)
Area of a Triangle = ½(Base)(Height)

Altitude of an Equilateral Triangle = (SquareRt(3))/2(Side)
Area of an Equilateral Triangle = (?3)/4(Side)(Side)

Area of a Right Triangle = ½(Leg A)(Leg B)

Hypotenuse Length of an Isosceles Right Triangle with Side "a" = a(SquareRt(2))

If the Shorter Leg of a 30°-60°-90° Triangle = "a"
Then The Longer Leg of the same Triangle = (SquareRt(3))(a)
And the Length of the Hypotenuse = 2(a)

pi = 3.141592653589793238462643383279502884197169399375105

Law of Sines: (Sine A)/a =(Sine B)/b = (Sine C)/c
Law of Cosines: In any triangle: c(c) = a(a) + b(b) - 2ab cos(C)

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