Chapter 7.5 Notes: Apply the Tangent Ratio

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Chapter 7.5 Notes Apply the Tangent Ratio

• Goal To use the tangent ratio to determine side
  lengths in triangles.

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• Using the Tangent Ratio
• A trigonometric ratio is a ratio of the lengths
  of two sides in a right triangle.
• You will use trigonometric ratios to find the
  measure of a side or an acute angle in a right
  triangle.
• The ratio of the lengths of the legs in a right
  triangle is constant for a given angle measure.
  This ratio is called the tangent of the angle.

3

• Ex.1 Find tan S and tan R. Write each answer as
  a fraction and as a decimal rounded to four
  decimal places.
• Ex.2 Find tan J and tan K. Round to four decimal
  places.

4

• Find the value of x. Round to the nearest tenth,
  if necessary.
• Ex.3 Ex.4

5

• Ex.5 Find the height h of the lamppost to the
  nearest inch.

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• Ex.6 A surveyor is standing 118 feet from the
  base of the Washington Monument. The surveyor
  measures the angle between the ground and the top
  of the monument to be 78o. Find the height, h, of
  the Washington Monument to the nearest foot.

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• Ex.7 Find the value of x. Round to the nearest
  tenth, if necessary.
• Ex.8 Find the value of x. Round to the nearest
  tenth, if necessary.
• 9
• 
  17o
• x

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• Ex.9 Find the tangent of a 60o angle.