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I have two problems that I'm not sure how to work out. :yuck:

1. You are driving to st louis, missouri and in the distance you see the gateway-to-the-west arch. this monument rises 192 m. you estimated your line of site to the top of the arch to be 2 degrees above horizontal. how far approximately (in km) are you from the base of the arch ?

OKay so i have the angle opening up to the right at 2 degrees, and the height of the leg in the opposite postion as 192 m. i tried to use sin 2 degrees * 192 meters = 6.70 m. i know that this is wrong already since in km, this number would be a lot smaller. the answer in the back of the book is 5.5km. i'm not sure what i'm doing wrong. i tried again, to use tan since it would be opposite, and it's the adjacent leg that i can't find. i get the same answer.

2. the silhouette of a christmas tree is an isoceles triangle. the angle at the top of the tree is 30.0 degrees, and the base measures 2.00 m across. How tall is the tree.

i tried a couple of things with this. first i tried the sin of 30 degrees * 2m and i know that the answer can't possibly be 1m. then i thought to maybe try tan since it is the adjacent leg i would be trying to get. the answer isn't 1.15 either. finally i tried to get the other angles at the bottom of the isoceles triangle as 75 degrees since triangles = 180 degrees, the top is 30 degrees, and the bottom two have to be equal. so then i tried the cos of 75 degress * 2 m and this didn't work either. the answer in the back of the book is 3.73m. thanks for the help.

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# Homework Help: Trig help

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