8.2 Special Right Triangles

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8.2 Special Right Triangles
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Theorem 8.5 45-45-90 Triangle Theorem

• In a 45-45-90 triangle, both legs are congruent
  and the length of the hypotenuse is time the
  length of a leg.
• Hypotenuse x leg

45
45
90
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Example 1

• Find the vale of each variable

90
9
45
45
x
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Practice 1

• Find the value of each variable

45
45
90
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Theorem 8.6 30-60-90 Triangle Theorem

• In a 30-60-90 triangle, the length of the
  hypotenuse is twice the length of the shorter
  leg. The length of the longer leg is times
  the length of the shorter leg.
• Hypotenuse 2 x shorter leg
• Longer leg x shorter leg

30
90
60
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Proof of 30-60-90
60
2s
2s
60
60
2s
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Example

• Find the value of the variable

30
5
f
60
90
d
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Classwork/Homework

• Pgs 428-429 1-8, 15, 21, 22
• Pgs 428-429 9-14,16-20