McGraw Hill Integrated II, 2012
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McGraw Hill Integrated II, 2012 View details
3. Special Right Triangles
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Exercise 49 Page 647

Let x be the smaller of the measures of the angles. Use the given ratio to rewrite the measures of the other two angles in terms of x. Did you get a special right triangle? If so, use the corresponding theorem.

37.9

Practice makes perfect

Let x, y, and z be the measures of the angles of the triangle. By the Triangle Angle-Sum Theorem, we have the following equation. x + y + z = 180^(∘) We are told that the ratio of the measure of the angles is 1:2:3, which leads us to the following relations. x = x y = 2x z = 3xLet's substitute the previous expressions into the first equation. x + 2x + 3x = 180^(∘) ⇒ x = 30^(∘) From the above, we conclude that the measure of the angles of our triangle are x=30^(∘), y=60^(∘), and z=90^(∘). Therefore, our triangle is a 30^(∘)-60^(∘)-90^(∘) triangle.

We also know that the shortest side is 8 units long. Therefore, the side opposite the 30^(∘) angle is 8 units long.

By applying the 30^(∘)-60^(∘)-90^(∘) Triangle Theorem, we have that the longer leg is 8sqrt(3) units long and the length of the hypotenuse is 16.

In conclusion, the perimeter of the triangle is 8 + 16 + 8sqrt(3) = 24+8sqrt(3) = 37.9.