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Problem Solving: Can you trust the diagram?
Yes, you can trust what you see. Figures are drawn to scale unless stated otherwise.
Data Sufficiency: Can you trust the diagram?
No. Figures are not necessarily drawn to scale and they may be drawn inaccurately to confuse you.
What is the property of a straight line?
A line is 180 degrees.
180 degrees = π
360 degrees = 2π

Intersecting Lines and the associated Angles
Perpendicular Lines
Two intersecting lines are perpendicular if the angle between them is 90 degrees.

Link:
en.wikipedia.org/wiki/Perpendicular

Parallel Lines
If two lines in a plane never intersect, they are parallel.

Link:
en.wikipedia.org/wiki/Parallel_(geometry)

Parallelogram
-Opposite sides are equal and parallel
-Opposite angles are equal
-Adjacent angles add up to 180 degrees
-Area = (base)(height)

Link:
en.wikipedia.org/wiki/Parallelogram

Triangle: What is the sum of the 3 angles in a triangle?
180 degrees
Triangle: What is the area of a triangle?
Area = 1/2(base)(height)
Triangles: What are the properties of an Equilateral triangle?
-Each side is equal to each other.
-Each angle is 60 degrees.
-All angles sum to 180 (60+60+60)

en.wikipedia.org/wiki/Equilateral_triangle
Triangle: What are the properties of an Isosceles triangle?
-Isosceles triangles have two equal sides.
-The two angles opposite those sides are equal.

Link:
en.wikipedia.org/wiki/Isosceles#Types_of_triangles
Triangle: What are the properties of a Right triangle?
-Right Triangles have one 90 degree angle.
-The side opposite the right angle is the Hypotenuse and it is the longest side.
-The other two sides are callled the legs.
-Pythagorean Theorem: a2 + b2 = c2

Link:
en.wikipedia.org/wiki/Right_triangle

Triangle: What are the Special Right Triangles?
30-60-90, sides = 1 : √3 : 2
45-45-90, side - 1 : 1 : √2

Link:
en.wikipedia.org/wiki/Special_right_triangles

What are some common Right Triangles?
-Right Triangle with sides of length 3-4-5
-Right Triangle with sides of length 6-8-10
-Right Triangle with sides of length 5-12-13

(These can be multiplied by anything to make them larger. For Example, multiply 3-4-5 by 3 to get 9-12-15)
Pythagorean Theorem?
You need one 90 degree right angle to use this equation!
Pythagorean Theorem: a2 + b2 = c2

What are the properties of a Rectangle?
-Area = Length x Width
-Perimeter = 2(L+W) = 2L+2W
-All Angles sum to 360

(Perimeter is the sum of all sides)
What are the properties of a Square?
-Area = (Side)2
-Perimeter = 4(Side)
-All Angles sum to 360

(Perimeter is the sum of all sides)
What are the properties of a Circle?
-Area = πr2
-Circumference = 2πr = πd
-Diameter = 2 x Radius
π = 180 Degrees ≈ 3.14... Radians
2π = 360 Degrees ≈ 6.28... Radians
π/2 = 90 Degrees ≈ 1.57... Radians

Circle: Equation for the Arc Length of a Circle (S)?
S = r x θ

S: Arc Length of the Circle
r: radius of circle
θ: central angle of circle, in radians 180 degrees = π radians = 3.14 radians 360 degrees = 2π radians = 6.28 radians
Thales' Theorem? (Triangle inscribed in a circle)
In geometry, Thales' theorem (named after Thales of Miletus) states that if A, B and C are points on a circle where the line AC is a diameter of the circle, then the angle ABC is a right angle.

One line MUST be the diameter!


Link:
http://en.wikipedia.org/wiki/Thales'_theorem
What is the Volume of a Rectangular Solid?
Volumerec = Length x Width x Height
(Width = Depth)

A side can have a length of 1.
What is the Volume of a Cube?
Volumesq = Side3
What is the Volume of a Cylinder?
Volumecyl = πr2h
What is the Surface Area of a Solid?
Surface Area of a solid is the sum of the areas of each side.
Coordinate Geometry? (x-y axis)
-The coordinate grid consists of a horizontal x-axis and a vertical y-axis.
-Coordinates are in the form (x,y).
-The origin is the intersection of the axes and has the coodinates (0,0).
-A line that rises from left to right has a positive slope.

-A line that rises from right to left has a negative slope.
-A horizontal line has a slope of 0, meaning x doesn't exist. For example, y=6 is a horizontal line at y=6.
What is the sum of in the interior angles of a polygon?
180(n-2)
n = number of sides of the polygon

Official Guide 12, pg 50, #10
What is the Fibonacci Sequence?
Haha... just kidding!
x of y cards