7.6 right triangles. ex 1) solve the right triangle that has c = 33 and b = 22 b a sketch the a,...
TRANSCRIPT
7.6 Right Triangles
Ex 1) Solve the right triangle that has c = 33 and B = 22
B
A
Sketch the
A, B, C = anglesa, b, c = sides (opp the )
22
90
180 90 22 68
B
C
A
C
All 3 ’sAll 3 sides
b
ac 22= 33
’s in a add to 180
Ex 1) Solve the right triangle that has c = 33 and B = 22
B
A
oppsin
hyp
sin 22 33sin 22 1233
adjcos
hyp
cos 22 33cos 22 3133
bB
c
bb
aB
c
aa
C
All 3 ’sAll 3 sides
b
ac
68
22
90
A
B
C
o
o
o
22
Use trig functions to find sides
= 33
SOH CAH TOA
31
12
33
a
b
c
68
Example 2
A guy wire on vert. utility pole is anchored at a point on level ground 18 feet from the base of the pole. If the wire makes an angle of 63 with ground, how long is the wire?
18cos63
1840 feet
cos63
x
x
x
63
18
Know adj sideNeed hypotenuse
CAH
Angles of Elevation & Depression
Line of sight
horizontalObserver
Angle of elevation
Object
Line of sight
horizontal
Observer Angle of depression
Object
Parallel Lines
Two Parallel Lines
alternate interior angles are congruent
cut by transversal
Example 3
From the top of a tower 300 feet high, the angle of depression of a rock is 35.7 Find the distance from base of tower to rock.
300tan35.7
300417.5 feet
tan35.7
x
x
300
x rock
35.7
Know opp sideNeed adj side
35.7
TOA
Homework
#718 Pg. 427 1 – 29 eoo,
33 – 41 odd