###
Surface Area of Cylinder

2πrh + 2πr^2

###
Surface area of Pyramid

1/2Pl + B

###
Surface Area of Cone

πrl + πr^2

###
Surface Area of Sphere

4πr^2

###
Volume of a Cylinder

πr^2h

###
Volume of a Pyramid

(1/3)Bh

###
Volume of a Cone

(1/3)πr^2h

###
Volume of a Sphere

(4/3)πr^3

###
Area of a Sector

(N/360)πr^2

###
Third Angle Theorem

If 2 angles of one triangle are congruent to two angles of a second triangle, the third angles of the triangle are congruent.

###
Circumcenter Theorem

The circumcenter of a triangle is equidistant from the vertices

###
Incenter Theorem

THe incenter of a triangle is equidistant from each side of the triangle

###
Centroid Theorem

The centroid of a triangle is located two thirds of the distance from a vertex to the midpoint of the side opposite the vertex on a median

###
Circumcenter

Point of concurrency of perpendicular bisectors

###
Incenter

point of concurrency of angle bisectors

###
Centroid

Point of concurrency for the medians of a triangle

###
Orthocenter

intersection point of altitudes

###
Isosceles Triangle Theorem

If 2 sides of a triangle are congruent, then the angles opposite those sides are congruent

###
SSS Similarity

if the measure of the corresponding sides of 2 triangles are proportional, then the triangles are similar

###
SAS Similarity

If the measure of 2 sides of a triangle are proportional to the measure of 2 corresponding sides of another triangle, and the included angles are congruent, then the triangles are similar

###
Triangle Proportionality Theorem

If a line is parallel to one side of a triangle and intersects the other 2 sides in 2 distinct points, then it separates these sides into segments of proportional lengths

###
Proportional Perimeters Theorem

If 2 triangles are similar, then the perimeters are proportional to measure of corresponding sides

###
Angle Bisector Theorem

An angle bisector in a triangle separates the opposite side into segments that have the same ratio as the other 2 sides

###
Law of Sines

(sin A)/a = (sin B)/b = (sin C)/c

###
Law of Cosines

a^2 = b^2 + c^2 - 2bc cos A

###
Parallelogram

Diagonals bisect, opposite sides congruent, consecutive angles supplementary, opposite angles congruent, one pair of opposite sides parallel and congruent

###
Rectangle

Same properties as parallelogram, diagonals are congruent

###
Rhombus

Diagonals are perpendicular, Each diagonal bisects 2 angles

###
Arc Length

(A/360) = (l/(2πr))

###
Equation of a circle

(x - h)^2 + (y - k)^2 = r^2

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