Question

In certain deep parts of oceans, the pressure of sea water, P, in pounds per square foot, at a depth of dfeet below the surface, is given by the following equation:4dP = 14 +11If a scientific team uses special equipment to measures the pressure under water and finds it to be 318pounds per square foot, at what depth is the team making their measurements?Answer: The team is measuring atfeet below the surface.

Answer 1

`836ft`

1) Given this equation for Pressure, we need to plug into p the pressure of 318 lbs/ft² to get the depth according to the model described by this equation.

2) So, we can write out:

`\begin{gathered} P=14+(4d)/(11) \\ 318=14+(4d)/(11) \\ 11*318=11*(14+(4d)/(11)) \\ 3498=154+4d \\ 3498-154=4d \\ 3344=4d \\ 4d=3344 \\ (4d)/(4)=(3344)/(4) \\ d=836ft \end{gathered}`

Note that we multiplied both sides by 11 to get rid of the fraction.

Thus this is the depth below the surface that generates such pressure