Chapter 10 Similarity
10­4 Proportions and Similar Triangles
Objective: Investigate proportional relationships in triangles.
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HW Solutions p. 508 # 13-23, not 19
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2.5
12 5/6 or 12.83
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12 m
220 yd
15.75 ft or 15 ft 9 in
90 ft
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Side-Splitter Theorem
If a line is parallel to one side of a triangle and intersects the other two sides, then it divides those sides proportionally.
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Example:
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Example:
PQ ll TR
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Corollary to the Side-Splitter Theorem
If three parallel lines intersect two transversals, then the segments intercepted on the transversals are proportional.
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Example: Find the value of x.
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Example: Find the value of x.
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Triangle-Angle Bisector Theorem
If a ray bisects an angle of a triangle, then it divides the opposite side into two segments that are proportional to the other two sides of the triangle.
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Example:
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Example:
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HW # 115
Prac 10-4
** Quiz on Tuesday!!
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