# Math

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Fred was measuring the height of a building. He stood standing at some distance from
the building and measured an angle of 38 degrees to the top of the building. He then
walked 100 feet further away from the building and measured an angle of 34 degrees to
the top.
How tall is the building?

I know I'm suppose to use tan

I got tan38=y/x from the first part of the information. I need help getting the second part

• Math -

from the outer triangle
tan 34 = y/(x+100)
y = (x+100)tan 34

y = xtan 38

so xtan 38 = (x+100)tan 34
xtan 38 = xtan 34 + 100tan 34
xtan 38 - xtan 34 = 100tan 34
x(tan 38 - tan 34) = 100tan 34
x = 100tan 34/(tan 38 - tan 34)

once you found x, you can find y using your first equation.

• Math -

you should help me mines is kinda like that and i don't understand it

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