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At a certain time of day the angle of elevation of the sun is 30 a tree has a shadow that is 25 feet long find the tree to the nearest foot

User Nasirkhan
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If we draw out this scenario, we can see that it is a 30-60-90 right triangle, and the tree shadow is the leg opposite of the 60 degree angle. The problem asks for the length of the tree, which is the leg opposite of the 30 degree angle. In a 30-60-90 triangle, the leg opposite of the 30 degree angle has length “x”, and the leg opposite of the 60 degree angle has length “x times sqrt 3” (or “x rad 3”). We know the leg opposite of the 60 degree angle is 25 feet, so we can setup the equation “x rad 3 = 25”. We divide sqrt of 3 on both sides and end up with “x = 25/sqrt 3”. The problem asked for the leg opposite of the 30 degree angle, which we set as “x”. The problem asks for the length to the nearest foot. When put into a calculator, “25/sqrt 3” ends up being about 14 feet, which is our final answer.
User Phil Kiener
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