Formula Reference Sheet
Perimeter of polygons or Circumference of circles.
Perimeter = 2 L + 2 W
--Or-P = 2 (L + W)
Units of measure are linear
To solve for the perimeter of any
shape, add the length of all the
sides.
C=d
or
C = 2r
P=a+b+c+d+e
Circumference= diameter times
Units of measure are linear
pi
--Or—
Circumference = 2 times the
radius times pi
If you are given the radius, then
Circumference = two times the radius
times pi
Units of measure are linear
Area of polygons and circles
Area = one-half the base times
the height
Area = length times height
sometimes we say
Area = base times height
A=bh
Units of measure are square
Units of measure are square
Area = one-half the height times the
sum of the bases.
Units of measure are square
Sometimes we have to divide shapes
into rectangles or triangles, find the
area of each part and then add them
together. A = 5 + 2 + 24
A = 31 square meters
Area = base times height
Units of measure are square
2
A=r
Area = radius squared times pi
If you are given the diameter,
divide d in half to solve for
radius and then substitute into
the formula for area.
A = Triangle + Rectangle
A = ½ (2)(2) + (4)(1)
A = 2 + 4 = 6 square units.
Units of measure are square
Surface Area of Prisms, cylinders, pyramids, cones and spheres
SA = 2 r
SA = 2 lw + 2 wh + 2lh
Surface Area = two times the
length times the width plus two
times the width times the height
plus two times the length times
the height.
Units of measure are square
2
+ 2rh
Surface Area = two times the
radius
squared times pi plus two
times the
radius times the height times
pi.
Pi (
) is approximately
equal to 3.14
Or
22
7
Units of measure are square.
Pyramid
SA 2bs b2
Surface Area = two times the length
of the square
base times the slant height of the
pyramid plus the
length of the square base times itself
(squared).
Units of measure are
square.
Sphere
SA= ½ Cs + B
SA = rsπ + r2π
Surface Area = one half the
circumference of the base times
the slant height plus the area of
the base
Surface Area = radius times the
slant height times pi plus the
area of the base
Surface Area = one half the
perimeter of the base times the
slant height plus the area of the
base.
If the base is a rectangle, then
SA = ½ (2L + 2W)s + L x W
-orSA = (L+W)s + LW
Units of measure are square
SA = 4 r2π
Surface Area = 4 times the radius
squared times pi.
Units of measure are square
Sphere
Units of measure are square
Volume = four-thirds times the radius
cubed times pi
Units of measure are cubic
Volume of Prisms, pyramids, cylinders, cones and spheres
V=
r2 h
Volume = l w h
Volume = radius squared times height times pi.
Volume = length times width times height
Units of measure are cubic
Units of measure are cubic
V
1 2
bh
3
Volume = one-third the length of the square base times
itself times the height
-OR- Multiply b squared times h then divide by 3.
Units of measure are cubic
V
1 2
r h
3
or
V
r 2h
3
Volume = one-third times the radius squared times
height times pi.
-ORMultiply the radius squared times height times pi
then divide by 3.
Units of measure are cubic