Download GEOMETRY Formulas and Definitions

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698-1579
CB 116
GEOMETRY Formulas and Definitions
FORMULAS:
Figure
Perimeter
Square
Rectangle
W
Area
P = L + W + L + W or
P = 4L (since all sides are equal)
A = LW or
A = L2 (since all sides are equal)
P=L+W+L+W
P = 2L + 2 W
A = LW
or
L
Parallelogram
P = L + W + L + W or
P = 2L + 2 W
A = LH (L is also referred to as the base)
A = bh
Triangle
P = S1 + S2 + S3
A = ½ S1H (S1 is also referred to as the base)
A = ½bh or
A=
Trapezoid
P = B1 + B2 + S1 +S2
A = ½ (B1 + B2)H
Circle
(also known as Circumference)
C = 2πr
A = πr2
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698-1579
CB 116
Figure
Volume
Surface Area
Cube
V = LWH
SA = LW + HL + WH + LW + HL + WH or
SA = 2LW + 2HL +2WH or
SA = 6L2 (since all sides are equal in a cube)
Rectangular Prism
V = LWH
SA = LW + HL + WH + LW + HL + WH
SA = 2LW + 2HL + 2WH
Sphere
V = 4/3 πr3
SA = 4πr2
Right Circular Cylinder
V = πr2h
SA = πr2 + πr2 + 2πrh
SA = 2πr2 + 2πrh
Right Cone
V = 1/3 πr2h
SA = πr2 + πrl
Pyramid
V = 1/3 LWH
SA = LW + ½ Lh + ½ Wh + ½ Lh + ½ Wh or
SA = LW + Lh + Wh (if W=L)
or
or
Math Learning Center Supplements
698-1579
CB 116
DEFINITIONS:
Acute angle: an angle whose measure is less than 90°
Area: the number of square units needed to cover a figure
Circle: set of points that are the same distance from some given point (the center)
Complementary Angles: two angles whose sum is 90°
Note that these two angles can be "pasted" together to form a right angle! A right angle is an angle with a measure of 90°
Diameter: the distance between two points on the circle, passing through the center
Equilateral Triangle: a triangle with three equal sides and three equal angles of 60° each
Hypotenuse: the side opposite the 90° angle in a triangle
Isosceles Triangle: triangle with two equal sides and two equal angles
Obtuse Angle: an angle whose measure is greater than 90° but less than 180°
Parallel Lines: two lines that never intersect
Parallelogram: a quadrilateral where the opposite sides area parallel and equal, the opposite interior angles are equal
Perimeter: the distance around a figure
Perpendicular Lines: two lines that intersect to create right angles
Pythagorean Theorem: (used only on right angles where a, b are legs and c is the hypotenuse)
Quadrilateral: a four sided figure; the sum of the interior angles have a measure of 360°
There are special types of quadrilaterals:
Revolution: an angle with a measure of 360° (a.k.a. a circle)
Radius: the distance from the center of a circle to a point on the circle
a2 + b2 = c2
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Similar Shapes: Shapes that have equal angles
Scalene Triangle: a triangle with no equal sides and no equal angles
Straight Angle: an angle with a measure of 180° (a.k.a. a line)
Supplementary Angles: two angles whose sum is 180°
Tangent: a line outside a circle or curve that intersects it in exactly one point
Transversal: a line that insects two other lines
Trapezoid: a quadrilateral whose opposite sides are parallel
Vertical Angles: Equal angles that are created by two intersecting lines
Volume: the number of cube units needed to fill a solid figure
698-1579
CB 116