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Area and Surface Formulas

Rectangle:
rectangler		 Area = Length X Width
A = lw

Perimeter = 2 X Lengths + 2 X Widths
P = 2l + 2w
Parallelogram:
parallelogramr

 Area = Base X Height
a = bh
Triangle:
triangler

 Area = 1/2 of the base X the height
a = 1/2 bh

Perimeter = a + b + c
(add the length of the three sides)

Trapezoid:
trapezoidr

 Perimeter = area + b1 + b2 + c
P = a + b1 + b2 + c
Circle:
circler

 The distance around the circle is a circumference. The distance across the circle is the diameter (d). The radius (r) is the distance from the center to a point on the circle. (Pi = 3.14) More about circles.
d = 2r
c = pd = 2 pr
A = pr2
(p=3.14)
Rectangular Solid:
RectangularPrismr

 Volume = Length X Width X Height
V = lwh
Surface = 2lw + 2lh + 2wh
Cylinder: Cylinderr

Volume = pr2 x height
V = pr2 h
Surface = 2p radius x height
S = 2prh + 2pr2
Pyramid: sbpyramidr

V = 1/3 bh
b is the area of the base
Surface Area: Add the area of the base to the sum of the areas of all of the triangular faces. The areas of the triangular faces will have different formulas for different shaped bases.
Cones: conerr

 Volume = 1/3 pr2 x height
V= 1/3 pr2h
Surface = pr2 + prs
S = pr2 + prs

Sphere:

spherer

 Volume = 4/3 pr3
V = 4/3 pr3
Surface = 4pr2
S = 4pr2