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.

Correct answer:

p =  1.4 %
α =  80.5 °

Step-by-step explanation:

$p=100\frac{6.5\cdot 3.9-25}{25}=1.4\%$

$\alpha =\arcsin (\frac{25}{6.5\cdot 3.9})=80.5^{\circ }$

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