Download Use a ruler to construct a triangle with the given side lengths. a. 1, 2

Use a ruler to construct a triangle with the given side lengths.
a. 1, 2, 5
b. 3, 2, 5
c. 4, 2, 5
Only c is possible. Why?
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Theorem 5­12 Triangle Inequality Theorem
The sum of the lengths of any 2 sides of a triangle is greater than the 3rd side.
Are the following triangles possible?
1. 5 8 20
2. 6
9
3
3. 6
9
4
4. State restrictions on the 3rd side.
x
11
5
2
5. ABC has sides of lengths 1 inch, 1 7/8 inches, and 2 1/8 inches and angles of 900, 280, and 620. Which side is opposite each angle measure?
In exercises 6­10, you are given an 18­inch piece of wire. You want to bend the wire to form a triangle so that the length of each side is a whole number of inches.
6. Name 4 ways to form an isosceles triangle.
7. Name a way to form an acute scalene triangle.
8. A triangle has sides of 11 centimeters and 17 centimeters. The third side must be greater than ? and less than ?.
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Homework
p. 331-334/6-14 E, 16-19,
22-26 E, 31, 33-34
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