how much water was in the pool orgininally?

To find how much water was in the pool originally, you need to write the function for how fast the water is leaving the pool.
Your function is
y=-8x+b
y is amount of water in the pool
x is how many hours
b is the original amount
Since you know y and x, plug those into the function.
132=-8(6)+b
132=-48+b
b=180
The original amount of water in the pool was 180 gallons.
I didn't mean to reanswer the question, I'm sorry! I didn't see that there was already an answer when I began answering.