8.
Pool X currently has 1,200 gallons of water and is being drained at a rate of 15 gallons per minute. Pool Y is currently empty and is being filled at a constant rate of 25 gallons per minute. Which inequality represents the situation when the amount of water in Pool Y is greater than the amount of water in Pool X?

1,200 - 15x > 25x

1,200 + 15x > 1,200 + 25x

1,200 - 15x < 25x

1,200 + 15x < 25x

What is the y-intercept of the graph of the linear function?

Pool X has 1200 gallons of water in it. It is being drained at a rate of 15 gallons per minute. If lowercase x is the number of minutes, then it has 1200-15x gallons left in the pool.

Consider after 1 minute we have x = 1, so,

1200-15x = 1200-15*1 = 1200-15 = 11185

Then after 2 minutes we have x = 2, which means,

1200-15x = 1200-15*2 = 1200-30 = 11170

is the amount left over in gallons.

----------------

In contrast, Pool Y is empty and we add 25 gallons per minute. So we start with 0 and add on 25x getting 0+25x = 25x as the expression representing the amount of gallons of water in Pool Y

-----------------

So we found these two expressions

1200-15x

25x

to represent the amount of water (in gallons) for Pool X and Pool Y respectively.

We want to know when Pool Y will have more water. So we get to this final answer

1200 - 15x < 25x

It is in the form A < B, where A is the amount of water in Pool X and B is the amount of water in Pool Y.