Download 10-23-15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook

10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
Date:
Lesson 8 Solve for Unknown Angles—Angles in a Triangle
Sep 23­4:15 PM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
DO NOW:
Find the measure of angle x in the figure to the right. Explain your calculations
Sep 23­4:17 PM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
Discussion
The sum of the 3 angle measures of any triangle is
.
In any triangle, the measure of the exterior angle is equal to the sum of the measures
of the
angles.
These are sometimes known as _________________________ angles.
Base angles of an
Each angle of an
__________
triangle are equal in measure.
__________ triangle has a measure equal to 60°.
Relevant Vocabulary
Isosceles Triangle: An isosceles triangle is a triangle with at least two sides of equal length.
Draw a figure for Isosceles Triangle and label accordingly.
Sep 23­4:18 PM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
Interior of a Triangle: A point lies in the interior of a triangle if it lies in the interior
of each of the angles of the triangle.
Exercises
1.
Find the measure of angle ‘a’ in the figure to the right. Justify your results.
Sep 23­4:19 PM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
In each figure, determine the measures of the unknown (labeled) angles.
Give reasons for your calculations.
Sep 23­4:20 PM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
Sep 23­4:22 PM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
Homework:
due 10/27/15
from lesson #5 & #8
AND from L.8 HW #3
Oct 26­8:31 AM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
Sep 23­4:23 PM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
Sep 23­4:23 PM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
Sep 23­4:24 PM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
Geometry M1L8 HW Solve for Unknown Angles in Triangles
Find the unknown (labeled) angle in each figure. Justify your calculations.
Sep 23­4:24 PM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
Sep 23­4:25 PM
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10­23­15 Geo M1L8 Solve for Unknown Angles in Triangles.notebook
October 26, 2015
Sep 23­4:25 PM
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