5.4EquilateralandIsoscelesTriangles
SpiralReview:Sketchandcorrectlylabelthefollowing.
SketchanEquilateralTriangle: SketchanIsoscelesTriangle:
UsingtheBaseAnglesTheorem:
Atriangleisisosceleswhenithasatleasttwocongruentsides.
Ifthereareonlytwocongruentsides,thenthesearecalledlegs.Theangleformedbythelegsisthevertexangle.ThethirdsideIsknownasthebase.ThetwoanglesadjacenttothebaseareKnownasthebaseangles.
Example1:Usingthebaseanglestheorem.
Example2:Measuresofatriangle
DeterminethemeasureofangleP,R,andQ.
Example3:UsingIsoscelesandEquilateralTriangles
Findthevaluesofxandyinthediagram.
Example4:Multistepproblem
Classwork/Homework
3-10,13-16,21,29,30,31,35