Transcript Slide 1

A surveyor is trying to measure the
distance across The Little Jay River. He
can’t stretch a measuring tape across it
(because it is too big), so he is going to
use trigonometry to find the distance. He
starts at point A along the bank of the river
that is directly west of a point C. He walks
50 feet north along the bank to point B.
He uses a special tool to find that the
angle to point C is now 33°. Use this
information to find the distance across the
river.
Start the problem by making a picture and
labeling what you know.
B
33°
50ft
A
x
C
AHe
surveyor
is
trying
to
measure
Use
uses
this ainformation
special
tool
to
to the
He
He
starts
walks
at
50
point
feet A
north
along
the
distance
across
Little
find
find
that
the
distance
the
angle
across
toThe
point
bank
along
ofthe
the
bank
river
tothat
point
is directly
B.
Jay
He can’t
C
the
isRiver.
river.
now
west
of a 33°.
point
C. stretch a
measuring tape across it
(because it is too big), so he is
going to use trigonometry to
find the distance.
Start the problem by making a picture and
labeling what you know.
33
xtheofx
Now just
What
istan
the
solve
measure
for

angle A if 1
variable.
we walked
50
directly north?
B
33°
x

50
tan33
From Angle 33, x is the ________
opp
50ft
A
x
C
x

32.47
From Angle 33, 50 is the ________
adj
Soriver
we are
going feet
to use
the _______
tan
The
is 32.47
across.
There is a building with a door that is 3
feet off the ground. In order to
accommodate all people that company
built a 21.5 foot long ramp up to the door.
Find the angle that the ramp makes with
the ground.
Start the problem by making a picture and
labeling what you know.
In
order
to aaccommodate
There
is
building
Find
What
the
angle
angle
does
thatthe
thewith
all
that
company
apeople
door
that
iswith
3 the
feet
ramp
building
makes
make
with
theoff
built
21.5 foot long
theaground.
3
ground.
ground?
ramp sin
up toxthe
 door.
21.5
3 ft
21.5 ft
x
1
sin
1
From angle x, 3 issin
the
______
opp
8.02
From anglexx,21.5
is the ______
hyp
The angle the ramp makes with
So weisneed
sin
the ground
8° to use ________