• Mar 15th 2011, 02:52 PM
IDontunderstand
A women entering an outside glass elevator on the ground floor of a hotel glances up to the top of the building across the street and notices that the angle of elevation is 48 degrees. She rides the elevator up 60 feet and finds the angle of elevation is 32 degrees. How tall is the building across the street?

is it 209 feet?

[x] / [sin(32)] = [x+60] / [sin(48)]

cross multiply and solve for x then add that to 60 to get the height, is that correct?
• Mar 15th 2011, 04:04 PM
pickslides
It seems like you are equating ratios here, is this because you want to use similar triangles?

Are the triangles in this scenario actually similar?
• Mar 15th 2011, 04:49 PM
IDontunderstand
Quote:

Originally Posted by pickslides
It seems like you are equating ratios here, is this because you want to use similar triangles?

Are the triangles in this scenario actually similar?

Well, the worksheet tells me to use the Law of Sines. The triangles cannot be similar since I have 2 angles (the angles of elevation) have different measurements. To be similar they have all angles similar.
• Mar 15th 2011, 05:09 PM
skeeter
Quote:

Originally Posted by IDontunderstand
A women entering an outside glass elevator on the ground floor of a hotel glances up to the top of the building across the street and notices that the angle of elevation is 48 degrees. She rides the elevator up 60 feet and finds the angle of elevation is 32 degrees. How tall is the building across the street?

is it 209 feet?

[x] / [sin(32)] = [x+60] / [sin(48)]

cross multiply and solve for x then add that to 60 to get the height, is that correct?

make a sketch ... make a sketch ... make a sketch

I'd use the law of sines to find the distance from the elevator bottom to the building top, then use the large right triangle to find the building height.

I get about 137' for the height.

btw ... did I say to make a sketch?
• Mar 16th 2011, 01:42 PM
IDontunderstand
My picture was all wrong. I see what I did wrong. Thanks
• Mar 17th 2011, 03:10 AM
HallsofIvy
Skeeter, do you think maybe it would be a good idea to make a sketch?