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This page provides a list of educational videos related to Angle Tangle. You can also use this page to find sample questions, apps, worksheets, lessons , infographics and presentations related to Angle Tangle.
Similar triangles 1
By Khan Academy
Sal reviews all the different ways we can determine that two triangles are similar. This is similar to the congruence criteria, only for similarity!
Solving problems with similar and congruent triangles
By Khan Academy
Sal uses the similarity of triangles and the congruence of others in this multi-step problem to find the area of a polygon.
Special right triangles
By Khan Academy
Showing the ratios of the sides of a 45-45-90 triangle are 1:1:sqrt(2)
Special right triangles
By Khan Academy
A few more 45-45-90 examples and an introduction to 30-60-90 triangles.
Special right triangles
By Khan Academy
Using what we know about 30-60-90 triangles to solve what at first seems to be a challenging problem
Solving similar triangles 1
By Khan Academy
Sal solves two problems where a missing side length is found by proving that triangles are similar and using this to find the measure.
Recognizing angles
By Khan Academy
Let's do a few example exercises in which you recognize and identify the type of given angle. This is a lot of fun!
Equation practice with congruent angles
By Khan Academy
Parallel lines, transversal lines, corresponding angles
Reason about the triangle congruence postulates
By Khan Academy
There are some cases when SSA can imply triangle congruence, but not always. This is why it's not like the other triangle congruence postulates/criteria.
Reason about the triangle congruence postulates
By Khan Academy
Sal introduces and justifies the SSS, SAS, ASA and AAS postulates for congruent triangles. He also shows that AAA is only good for similarity. For SSA, better to watch next video.
Reason about the triangle congruence postulates
By Khan Academy
Sal explains what it means for triangles to be congruent and what is a postulate/axiom. He also presents the SSS congruence postulate/criterion and its justification.
Measuring angles using a protractor | Angles and intersecting lines | Geometry | Khan Academy
By Khan Academy
Let's use our virtual protractor to measure some angles together, shall we?
Quadrilateral angles
By Khan Academy
Sal proves that opposite angles of a parallelogram are congruent.