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#1 2007-08-05 17:55:03
- natashabaker
- Member
- Registered: 2007-05-25
- Posts: 10
geometry and trig
Elise and David were attempting to find the width of a river. Here is Elise's sketch including the measurements they had made:
How wide is the river (to the nearest meter)?
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#2 2007-08-05 19:04:04
- JaneFairfax
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- Registered: 2007-02-23
- Posts: 6,868
Re: geometry and trig
If the width of the river is x m,
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#3 2007-08-05 19:13:16
- natashabaker
- Member
- Registered: 2007-05-25
- Posts: 10
Re: geometry and trig
thanks although i thought tan was used to find the degree, i was using cos 
, oh and how wouldi type that in the calculator to work it out?
Last edited by natashabaker (2007-08-05 19:18:21)
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#4 2007-08-06 23:05:07
- George,Y
- Member
- Registered: 2006-03-12
- Posts: 1,379
Re: geometry and trig
tan25 =
*120=
-15=
the answer
X'(y-Xβ)=0
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