1. 9.2 Notes: Solving Right Triangles

2. What does it mean to solve a right triangle? If we are asked to solve a right triangle, we want to know the values of ALL sides and ALL angles. A few reminders: 1) The total degrees inside a triangle is 180°. 2) Always check that your calculator is in DEGREE mode! 3) Lower case letters are side lengths, upper case letters are angle measures.

3. Let’s take a look at your calculator: You will need the following buttons on your calculator to solve for the ANGLE MEASURE: TanSinCos When we push one of these buttons and enter a number value, we get the value of the angle measure (in degrees). A) tan 30B) sin 68C) cos 127

4. Let’s try some: EX 1: A = 20°, b = 7, find a EX 2: B = 55°, b = 13, find c

5. EX 3: Solve the triangle when B = 68°, a = 5. EX 4: Solve the triangle when A = 32°, b = 10

6. Story problems….YAY EX 5: A tree casts a shadow 205 feet long. The angle of elevation from the shadow to the sun is 25°. Find the height of the tree. a) Draw a picture b) label what you know c) determine which trig function to use to find the solution.

7. EX 6: You are standing 200 feet from the bases of a redwood tree. You estimate the angle of elevation to the top of the tree is 60°. What is the approximate height of the tree? a) Draw a picture b) label what you know c) determine which trig function to use to find the solution.