Answer: 40minutes
Explanation:
the equation y=15x+ 600 represents the relationship between the time (in minutes) it takes for a tank to be emptied (y) and the number of minutes (x) that have passed.
To find out after how many minutes the tank will be empty, we need to find the value of x when y equals zero. This is because when y is zero, it means the tank is empty.
Setting y to zero in the equation, we get:
0 = -15x + 600
To solve for x, we need to isolate the variable. Let's subtract 600 from both sides of the equation:
-15x = -600
Next, let's divide both sides of the equation by -15:
x = 40
Therefore, after 40 minutes, the tank will be empty.