Download Math 10 Ch 3. Right Triangle Trigonometry Lesson 3

Math 10
Ch 3. Right Triangle Trigonometry
Lesson 3-5
Lesson 3-5: Solving Right Triangles
Recap: In the following triangle label the Hypotenuse, Opposite and Adjacent sides, from the point of view of angle A.
A
SinA =
B
C
CosA =
Tan A=
Calculator Check: cos 60  0.5
Standard for rounding, unless otherwise stated:
Lengths –
Angles –
Ex. #1 To determine the measure of each indicated angle, which trigonometric ratio would you use? Why?
a)
b)
c)
Ex. #2 Determine the length of each indicated side to the nearest tenth of a centimeter.
a)
b)
c)
Ex. #3 Find the measure of A
Homework pg. 131 #1, 4, 5-8
1
Ex. #4 Solve each right triangle.
a)
b) DEF where E  90 , DE  9 in., DF  12 in.
Recap: Angle of Depression, Angle of Elevation
Ex. #5 The world’s tallest totem pole is in Alert Bay, B.C., home of the Nimpkish First Nation. Twenty feet from the
base of the totem pole, the angle of elevation of the top of the pole is 83.4 . How tall is the totem pole to the
nearest foot?
Homework pg. 131 #1, 4, 5-8