7.3 Use Similar Right Triangles

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7.3 Use Similar Right Triangles

• Before You identified altitudes of a triangle.
• Now You will use properties of the altitude in
  right triangles.
• Why So you can determine the height of an object.

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Theorem 7.5

• If an altitude is drawn to the hypotenuse of a
  right triangle, then the two triangles formed are
  similar to the original triangle and to each
  other.

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Identify the three similar triangles in the
diagram
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Your turn

• Identify the three similar right triangles in the
  given diagrams.

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Find the length of the altitude

• Step 1 Identify the three similar triangles
  created by the altitude and sketch them.
• Step 2 Write a proportion to find the value of
  h.
• In similar figures corresponding sides are
  proportional

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Identify the similar triangles. Then find the
value of x.

• Sketch the 3 similar triangles.
• Write a proportion to find x.

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Geometric Mean

•  

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Geometric Mean (Altitude) Theorem

• The length of the altitude is the geometric mean
  of the lengths of the hypotenuse segments

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Geometric Mean (Leg) Theorem

• The length of each leg is the geometric mean of
  the lengths of the hypotenuse and the adjacent
  hypotenuse segment.

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Proportions Involving Geometric Means in Right
?ABC
http//www.youtube.com/watch?vPXBFDBmBP0I
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Find the value of y

• Geometric Mean Formulas
• Label the parts and use the formula to create a
  proportion.
• Solve for the variable.
• Triangle Similarity
• Identify the 3 similar triangles and sketch them.
• Write a proportion
• Solve for the variable.

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Your Turn

• Find the value of the variable.

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Assignment

• Pg 453 1-9 odd, 13-23 odd, 29
• Quiz 7.1-7.3 next class period