What is an equation of the line that passes through the point (6,-4) and is perpendicular to the line 2x-y=5

The decibel level of sound is 50 db greater on a busy street than in a quiet room where the intensity of sound is watt/m2. the level of sound in the quiet room is db, and the intensity of sound in the busy street is watt/m2. use the formula , where is the sound level in decibels, i is the intensity of sound, and is the smallest sound intensity that can be heard by the human ear (roughly equal to watts/m2).

For each proportion find the unknown number x 1/5/8=×/15

41/17 as a decimal rounded to the nearest hundredth