SOLUTION: the area of a triangle is 8346 sqm. and two of its interior angles are 37°25' and 56°17'. What is the length of the longest side?

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Question 869796: the area of a triangle is 8346 sqm. and two of its interior angles are 37°25' and 56°17'. What is the length of the longest side?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Let's call the missing angle X, and the other two angles
Y=56%5Eo17%22+%27%22 and Z=37%5Eo25%22+%27%22 .
The measure of the third angle is
X=180%5Eo-%22%28%2237%5Eo25%22+%27+%22%22%2B%2256%5Eo17%22+%27+%29+=%22180%5Eo-92%5Eo32%22+%27+=%2286%5Eo18%22+%27+%22 .
X=86%5Eo18%22+%27+%22 is the largest angle.

As customary, we call the side opposite each angle (and its length) with the same letter as the opposite angle, but lowercase instead of capital:
x= length (in meters) of he longest side (the one opposite largest angle X),
x= length (in meters) of he shortest side (the one opposite smallest angle Z), and
y= length (in meters) of he medium-sized side (the one opposite medium-sized angle Y).

The sines of the angles rounded to 4 decimal places are:
sin%28X%29=0.9979
sin%28Y%29=0.8138
sin%28Z%29=0.6076

Law of sines states that
x%2Fsin%28X%29=y%2Fsin%28Y%29=z%2Fsin%28Z%29 .
Substituting the values of the sines of the angles rounded to 4 decimal places:
x%2F0.9979=y%2F0.8318=z%2F0.6076 .
From those equations we can solve for y and z as functions of x :
y%2F0.8318=x%2F0.9979-->y=0.8318x%2F0.9979
z%2F0.6076=x%2F0.9979%7D%7D--%3E%7B%7B%7Bz=0.6076x%2F0.9979

We know that the area of a triangle XYZ can be calculated from the length of two sides and the sine of the angle between them as
area%5BXYZ%5D=%281%2F2%29%2Ay%2Az%2Asin%28X%29
and we know that area%5BXYZ%5D=8346 square meters
so substituting the values/expressions used/found above,
8436=%281%2F2%29%2A%280.8318x%2F0.9979%29%2A%280.6076x%2F0.9979%29%2A0.9979
8436=0.8318%2A0.6076%2Ax%5E2%2F%282%2A0.9979%29
2%2A0.9979%2A8436%2F%280.8318%2A0.6076%29=x%5E2
x=sqrt%282%2A0.9979%2A8436%2F%280.8318%2A0.6076%29%29
x=181.54meters (rounded)