A submarine is 105 ft below the surface of the water, and it begins to ascend at a rate of 3 ft per min. After how many min will the submarine be 82 ft below the surface??? Plzzz I will give you 100 points

Respuesta :

Answer:

7 2/3 minutes

Step-by-step explanation:

We can write this equation in y = mx+b form

where m = 3 ft/min and b = -105 ft  

x is the number of minutes and y is the depth

y = 3 * x -105

We want to find when y = -82

-82 = 3x -105

Add 105 to each side

-82+105 = 3x-105+105

23=3x

Divide by 3

23/3 = 3x/3

23/3=x

Changing into a mixed number

3 goes into 23  7 times with 2 left over

7 2/3 minutes