Circle
ShapeArea = πr²
Circumference = 2πr
Diameter = 2r
Rectangle
ShapeArea = l × w
Perimeter = 2(l + w)
Diagonal = √(l² + w²)
Triangle
ShapeArea = ½ × base × height
Perimeter = a + b + c
Heron's: A = √(s(s-a)(s-b)(s-c))
Square
ShapeArea = s²
Perimeter = 4s
Diagonal = s√2
Sphere
ShapeVolume = (4/3)πr³
Surface Area = 4πr²
Cylinder
ShapeVolume = πr²h
Lateral Area = 2πrh
Total Area = 2πr(r+h)
Cone
ShapeVolume = (1/3)πr²h
Slant height = √(r²+h²)
Lateral Area = πrl
Trapezoid
ShapeArea = ½(a+b)h
Perimeter = a+b+c+d