1. Holt Geometry 8-3 Solving Right Triangles Use trigonometric ratios to find angle measures in right triangles and to solve real-world problems. Objective

2. Consider this! Hobie is racing up a ramp with a grade of 38%. To the nearest degree, what angle does the ramp make with the ground? Note: A 38% grade means the ramp rises (or falls) 38 ft for every 100 ft of horizontal distance. 100 ft 38 ft AB C What trig ratio would involve angle A, 38, and 100? Using guess/check, find m<A, to the nearest tenth!

3. Holt Geometry 8-3 Solving Right Triangles Find the angle whose sine is 0.335

4. Holt Geometry 8-3 Solving Right Triangles Find the unknown measures. Round lengths to the nearest hundredth and angle measures to the nearest degree.

5. Remember this? Baldwin St. in Dunedin, New Zealand, is the steepest street in the world. It has a grade of 38%. To the nearest degree, what angle does Baldwin St. make with a horizontal line? Note: A 38% grade means the road rises (or falls) 38 ft for every 100 ft of horizontal distance. 100 ft 38 ft AB C What trig ratio would involve angle A, 38, and 100? Use your calculator to find m<A, to the nearest tenth!

6. Now, let’s put our triangle on a graph! The coordinates of the vertices of ∆PQR are P(–3, 3) Q(2, 3) R(–3, –4) Find the side lengths to the nearest hundredth and the angle measures to the nearest degree.

7. Lesson Quiz: 1. Evaluate cos -1 (0.97) 2. Find the measures of <D and <F. 14° mD  68° mF  22° 3. A highway sign warns that a section of road ahead has a 7% grade. To the nearest degree, what angle does the road make with a horizontal line?