10 2 Area of triangles and trapezoids - Math...
Transcript of 10 2 Area of triangles and trapezoids - Math...
AreaofTrianglesandTrapezoids Name:Pre-Algebra Date:Chapter10–Lesson2Pre-Algebra Date:Chapter10–Lesson2
Moreresourcescanbefoundonourclasswebsite:www.elliottsttims.weebly.com/resources
AreaofTriangles Everyparallelogramcanbedividedinto2congruenttriangles.
TheareaofeachtriangleisHALFtheareaoftheparallelogram.Theformulaforareaofatriangleis:
𝐴∆ =12 𝑏ℎ
whereb=baseandh=heightTheheightisdefinedastheperpendiculardistancefromonevertexofthetriangletoitsoppositeside.
Example:Findtheareaofthistriangle:
𝐴 =
12 𝑏ℎ
𝐴 =12 14 5
𝐴 = 35 𝑠𝑞𝑢𝑎𝑟𝑒 𝑢𝑛𝑖𝑡𝑠
AreaofTrapezoids Theformulafortheareaofatrapezoidis:
𝐴!"#$ =12 ℎ (𝑏! + 𝑏!)
whereh=height𝑏!=lengthofoneofthebases𝑏!=lengthoftheotherbase
AreaofTrianglesandTrapezoids Name:Pre-Algebra Date:Chapter10–Lesson2Pre-Algebra Date:Chapter10–Lesson2
Moreresourcescanbefoundonourclasswebsite:www.elliottsttims.weebly.com/resources
Example:
𝐴 =
12ℎ (𝑏! + 𝑏!)
𝐴 =12 4 (10+ 6)
𝐴 =12 4 (16)
𝐴 = 32 𝑠𝑞𝑢𝑎𝑟𝑒 𝑢𝑛𝑖𝑡𝑠