A room is 12m long, 9m wide and 8m high. Find the cosine of the angle which a diagonal of the room makes with the floor of the room.

A room is 12m long, 9m wide and 8m high. Find the cosine of the angle which a diagonal of the room makes with the floor of the room.

Answer Details

${\mathrm{a2=122+92\; a\; 2\; =\; 12\; 2\; +\; 9\; 2\; a=\surd 122+92\; a\; =\; 12\; 2\; +\; 9\; 2\; a=15 m\; a\; =\; 15\; m\; b2=152+82\; b\; 2\; =\; 15\; 2\; +\; 8\; 2\; b=\surd 152+82\; b\; =\; 15\; 2\; +\; 8\; 2\; b=17 m\; b\; =\; 17\; m\; cos\theta =ab=1517}}^{}$