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 #1
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Anonymous...this problem is quite a bit more difficult than the previous ones you have submitted.....I'll explain it...if you have trouble...let me know...it requires some "substitutions"

First.....as the woman looks at the pole...let's call the the opposite side to the angle of depression, "x"......this "x" represents only a part of the pole height that is below her sight line....so we have

tan(14) = x/d   where "d" is the distance the woman is from the pole ...this means that  

d = x/tan(14)

Now.........the part of the pole that is above her sight line is just 40-x...so using the angle of elevation and the tangent again, we have

tan(18) = (40-x)/d

Now....because  I want an equation in one variable, I'm going to substitute x/tan(14) for "d"in this second equation...so we have

tan(18) = (40-x)/ (x / tan(14))      ...  multiply both sides by (x/tan(14))..this gives

tan(18) (x / tan(14) = (40-x)         .... doing a little "rearranging" we have

[tan (18) / tan (14)] x   = 40- x      ......divide tan(18) by tan(14) = 1.303

1.303x = 40 -x                              .......add x to both sides

2.303x = 40                                  ........divide both sides by 2.303

x = 40/2.303 = 17.37                     this "x" represents the height of the pole below her sight line........but that's not what we're after...we want "d"...so using d = x/tan(14), we have

d = 17.37 / tan(14) = 69.7 ft.......and that's her distance from the pole

 

I realize you might get "stuck" on this one.......let me know....

 

2 Jun 2014