Search "triangle"
30-60-90 triangle example problem
Using what we know about 30-60-0 triangles to solve what at first seems to be a challenging problem
Khan Academy
Special right triangles
562
06:39
Congruent legs and base angles of isosceles triangles
Showing that congruent legs imply equal base angles and vice versa
Area of an equilateral triangle
Finding the formula for the area of an equilateral triangle with side s
Khan Academy
Perimeter and area of triangles
660
03:42
Area of diagonal generated triangles of rectangle are equal
Area of Diagonal Generated Triangles of Rectangle are Equal
Khan Academy
Perimeter and area of triangles
531
04:35
Triangle area proofs
Proving that the area of any triangle is 1/2 b x h
Khan Academy
Perimeter and area of triangles
501
10:22
Figuring out all the angles for congruent triangles example
Another example of using congruency to figure out a bunch of angles
Example involving an isosceles triangle and parallel lines
Integrating what we know about isosceles triangles and parallel lines
Equilateral triangle sides and angles congruent
Showing that all of the angles of an equilateral triangle are 60 degrees
Congruent triangle example 2
Showing that segments have the same length
Khan Academy
Congruence postulates
507
12:13
30-60-90 triangle side ratios proof
Proving the ratios between the sides of a 30-60-90 triangle
Khan Academy
Special right triangles
518
06:58
Finding congruent triangles
Using the SSS, ASA, SAS, and AAS postulates to find congruent triangles
Khan Academy
Congruence postulates
454
07:27
Other triangle congruence postulates
SSS, SAS, ASA and AAS postulates for congruent triangles. Showing AAA is only good for similarity and SSA is good for neither
Khan Academy
Congruence postulates
569
13:27
Proof: Sum of measures of angles in a triangle are 180
Proof that the sum of the measures of the angles in a triangle are 180
Triangle angle example 3
Multiple ways to solve for the angles of multiple triangles
Khan Academy
Triangle angles
496
05:41
Triangle angle example 2
Another example finding angles in triangles
Khan Academy
Triangle angles
508
04:54
Challenging triangle angle problem
Interesting problem finding the sums of particular exterior angles of an irregular pentagon
Khan Academy
Triangle angles
493
06:24
45-45-90 triangle side ratios
Showing the ratios of the sides of a 45-45-90 triangle are 1:1:sqrt(2)
Khan Academy
Special right triangles
519
05:41
Area of an equilateral triangle
Finding the formula for the area of an equilateral triangle with side s
Khan Academy
Koch snowflake fractal
578
03:42
