A plane can fly 360 mph in still air. If it can fly 210 miles downwind in the same amount of time it can fly 150 miles upwind, find the velocity of the wind. mph

What is x and y (use substitution? ) 5x+3y=38 and y=3x+8?

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).

Brent wants to know what is 5 x 1/2