# Triangles I Definition Polygon a closed many straightsided figure. Copyright 2000 by Monica Yuskaitis Definition Angle two rays that meet at a common end point. Copyright 2000 by Monica Yuskaitis Definition

Degree a unit of measurement of an angle or arc, represented by the symbol . 90 Copyright 2000 by Monica Yuskaitis Definition Quadrilateral a polygon with 4 angles and 4 straight sides. Copyright 2000 by Monica Yuskaitis

Quadrilateral Family parallelogram trapezoid rhombus rectangle square Copyright 2000 by Monica Yuskaitis

Property of quadrilaterals The sum of all the angles equals 360 degrees. 90 90 90 90

Copyright 2000 by Monica Yuskaitis Property of Quadrilaterals The sum of all the angles equals 360 degrees. 90 90 90 90 90 + 90 90

90 360 Copyright 2000 by Monica Yuskaitis Property of Quadrilaterals The sum of all the angles equals 360 degrees. 90 90 90 90 90 + 90

90 90 360 Copyright 2000 by Monica Yuskaitis Property of Quadrilaterals The sum of all the angles equals 360 degrees. 70 70 70 70 110 + 110

110 110 360 Copyright 2000 by Monica Yuskaitis Property of Quadrilaterals The sum of all the angles equals 360 degrees. 65 65 115 65 115 + 115

65 115 360 Copyright 2000 by Monica Yuskaitis What is the missing angle? 90 90 90 ?

Copyright 2000 by Monica Yuskaitis 90 90 90 + ? 360 What is the missing angle? 70

70 ? 110 Copyright 2000 by Monica Yuskaitis 70 70 110 + ?

360 What is the missing angle? ? 65 65 115 65 65 115

+ ? 360 Copyright 2000 by Monica Yuskaitis What is the missing angle? 90 ? 90 90 Copyright 2000 by Monica Yuskaitis

90 90 90 + ? 360 What is the missing angle? 109 58 ?

81 58 81 109 + ? 360 Copyright 2000 by Monica Yuskaitis