Download Inequalities in Triangles

5­2
Inequalities and Triangles
Exterior Angle Inequality Theorem: If an angle is an exterior
angle of a triangle, then its measure is greater than the
measure of either of its corresponding remote interior
angles.
Ex.
1
Ex. State all angles whose measures are less than m∠1.
1.
2.
2
Theorem: If one side of a triangle is longer than another side,
then the angle opposite the longer side has a greater measure
than the angle opposite the shorter side.
Ex.
3
Ex. Determine the relationship between the given angles.
4
Theorem: If one angle of a triangle has a greater measure
than another angle, then the side opposite the greater angle is
longer than the side opposite the lesser angle.
Ex.
AC > AB > BC
5
Ex. Determine the relationship between the given sides.
6
HW: p251­252 #4­6, 10­12,
18­22 even, 30­34 even,
38­42 even, 46­50 even
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