Download math424jan7.notebook 1 January 07, 2014 Happy 2014

math424jan7.notebook
January 07, 2014
hw due Wed. Bumby p. 156# 2­10 challenge 1 p. 159 written 1­23 odd Jurgenson p. 97 # 8,9,10, 14,15,16,23,24
We will have an assessment Monday January 27.
Happy 2014
Theorem: the sum of the measures of the angles of a triangle is 180 degrees.
A corollary is a theorem that follows easily from another theorem.
B
The angle formed by the extension of one side of a triangle and a side of the triangle is called an exterior angle of the triangle.
A
C
D
Angle BCD is an exterior angle of triangle ABC. Angles A and B are called the remote interior angles.
Any side can be extended to form exterior angles of the triangle.
(or any polygon for that matter)
Theorem: (exterior angle theorem) The measure of an exterior angle of a triangle is equal to the sum of the measures of its two remote interior angles.
Corollaries to "The sum of the measures of the angles of a triangle is 180 degrees"
If 2 angles in one triangle are congruent to 2 angles in another triangle, then the third angles are congruent.
In a triangle, there can be no more than one right angle or one obtuse angle.
The acute angles of a right triangle are complementary.
Each angle of an equiangular triangle is 60 degrees.
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math424jan7.notebook
January 07, 2014
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math424jan7.notebook
January 07, 2014
Identify exterior angles in the diagram below, use the exterior angle theorem to show the relationship between the angle
and its remote interior angles.
8
C
7
6
B
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math424jan7.notebook
January 07, 2014
A polygon is a closed figure made of coplanar segments (called sides) so that
each segment intersects exactly 2 other segments, one at each endpoint and no two segments with a common endpoint are collinear.
A convex polygon is a polygon such that no line containing a side of the polygon contains a point in the interior of the polygon.
A segment joining 2 nonconsecutive vertices is called a diagonal of the polygon
Regular polygon: a polygon that is equiangular and equilateral.
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