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What are the angle measures of the triangle? the sides are 21, 7 sqrt 3 and 14 sqrt 3
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Please notice on how I edited your post in order for to make sense.
Solution
Notice that
+ = 49*3 + 441 = 147 + 441 = 588= 3*196 = = .
Thus the triangle with the side lengths of 21, and is a right angled triangle
with the legs 21 and and the hypotenuse of .
Also, the leg is half length of the hypotenuse .
Therefore, the given triangle is (30°, 60°, 90°)- triangle.
Its angles are 30°, 60° and 90°.
Solved.