



 
Hi Penny, I got for the length of the third side to be slightly different than what you got. I got 147.29 feet. Here is what I did. First I let the length of the diagonal from sw to ne be c feet. I then used the Law of Cosines on the triangle with vertices ne, sw and se to get
This gave me c = 135.98 feet. Next I used the Law of Sines on the triangle with vertices ne, nw and sw. If the measure of the angle from sw to ne to nw is θ degrees then
Solving for sin(θ) I got sin(θ) = 0.3670 and then the inverse sine function on my calculator gave θ = 21.53 degrees. Thus the measure of the angle from nw to sw to ne is 180  67.38  21.53 = 91.09 degrees. Using the Law of Sines again with d the length of the side from ne to nw
and solving for d gave 147.29 feet. Harley  


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