how to review ap us history 145 videos

Using a Protractor
Geometry Geometry Building Blocks
How to use a protractor to measure an angle.
protractor angle acute obtuse right 
Using Sine to Calculate the Area of a Triangle
Geometry Basic Trigonometry
How to calculate the area of any triangle using two sides and an included angle.
area of a triangle sine 
Using the Pythagorean Theorem to find a Missing Hypotenuse
Geometry Pythagorean Theorem
How to calculate the hypotenuse in a right triangle given the lengths of the legs using the Pythagorean Theorem.
Pythagorean theorem leg hypotenuse right triangle 
Using the Pythagorean Theorem to find a Missing Leg
Geometry Pythagorean Theorem
How to use the Pythagorean Theorem to find a missing leg, given the length of the hypotenuse and a leg.
Pythagorean theorem leg hypotenuse right triangle 
The Law of Cosines
Geometry Basic Trigonometry
How to define and use the law of cosines.
law of cosines ratios triangles 
Counterexample
Geometry Geometry Building Blocks
How to use a counterexample to prove a definition or conjecture incorrect.
counterexample definition conjecture 
Duplicating a Line Segment
Geometry Constructions
How to duplicate a line segment using a compass and straightedge.
congruent segments construction compass straightedge 
Duplicating an Angle
Geometry Constructions
How to duplicate an angle using a compass and straightedge.
congruent angles construction compass straightedge 
Constructing the Incenter
Geometry Constructions
How to construct the incenter using a compass and straightedge.
point of concurrency angle bisectors equidistant 
Constructing the Circumcenter
Geometry Constructions
How to construct the circumcenter using a compass and straightedge.
point of concurrency perpendicular bisectors equidistant circumscribed construction 
Locus and Definition of a Circle and Sphere
Geometry Circles
How to define a circle and a sphere using the word locus.
locus set of points distance plane circle sphere given 
Equation of a Circle
Geometry Pythagorean Theorem
How to derive the equation for a circle using the distance formula.
distance formula radius center circle 
Similarity Shortcuts
Geometry Similarity
How to determine if two triangles are similar using a shortcut.
similar triangles AA SAS SSS proportion congruence 
Indirect Measurement
Geometry Similarity
How to use similar triangles to measure the height of objects.
indirect measurement similar triangles measurement 
Converse of the Pythagorean Theorem
Geometry Pythagorean Theorem
How to use the converse of the Pythagorean Theorem to determine if a triangle is a right triangle, how to use Pythagorean triples to memorize the lengths of certain right triangles.
right triangle leg hypotenuse converse Pythagorean triples 
Constructing Parallel Lines
Geometry Constructions
How to construct parallel lines using three different methods.
transversal duplicating angles corresponding alternate interior alternate exterior 
SSS and SAS
Geometry Triangles
How to use the SAS and SSS shortcuts to determine the congruence of two triangles.
triangle congruence side side side side angle side 
ASA and AAS
Geometry Triangles
How to use the ASA and AAS shortcuts to determine the congruence of two triangles.
triangle congruence angle side angle angle angle side 
HL
Geometry Triangles
How to use the hypotenuse leg shortcut to determine the congruence of right triangles.
hypotenuse leg triangle congruence right triangles 
CPCTC
Geometry Triangles
How to use the principle that corresponding parts of congruent triangles are congruent, or CPCTC.
corresponding parts or congruent triangles proofs