Example 3

A right triangle has a hypotenuse of 5 and a side length of 2. Find the angle measurements and the unknown side length. Find the sine, cosine, and tangent for both angles. Without drawing another triangle, compare the trigonometric ratios of with those of a triangle that has been dilated by a factor of .
  1. First, draw the triangle with a ruler, and label the side lengths and angles.
  2. Find by using the Pythagorean Theorem.
  3. Use a protractor to measure one of the acute angles, and then use that measurement to find the other acute angle.
  4. Find the sine, cosine, and tangent ratios for both acute angles. Express your answer in decimal form to the nearest thousandth.
  5. Without drawing a triangle, find the sine, cosine, and tangent for a triangle that has a scale factor of 3 to . Compare the trigonometric ratios for the two triangles.
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