# Black building

Keith built building with a rectangular shape 6.5 m × 3.9 m. Calculate how much percent exceeded the limit 25 m2 for small building. Building not built in accordance with the law is called "black building". Calculate the angle that the walls were clenching each other to meet limit footprint limit 25 m2 with given lengths of the walls, if it stands angular.

Result

p =  1.4 %
α =  80.5 °

#### Solution:

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Our percentage calculator will help you quickly calculate various typical tasks with percentages. Most natural application of trigonometry and trigonometric functions is a calculation of the triangles. Common and less common calculations of different types of triangles offers our triangle calculator. Word trigonometry comes from Greek and literally means triangle calculation.

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