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Perimeter and area basics

Khan Academy
Perimeter and area of triangles
486
08:24

Triangle area proofs

Proving that the area of any triangle is 1/2 b x h

Khan Academy
Perimeter and area of triangles
551
10:22

Interesting perimeter and area problems

Three example problems involving perimeter and area

Khan Academy
Perimeter and area of triangles
564
08:12

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
572
04:35

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
696
03:42

Area of shaded region made from equilateral triangles

Khan Academy
Perimeter and area of triangles
647
05:36

Challenging perimeter problem

Perimeter of rectangle covered by 9 non-overlapping squares. From 200) American Invitational Math Exam

Khan Academy
Perimeter and area of triangles
691
09:55