A) s(300) = 500
x = hours
x = 300
300 = 500
The only thing you could factor out is X so it would be
X(4x-5)
X + y = 40.....multiply by -4
4x + 6y = 180
-------------------
-4x - 4y = -160 (result of multiplying by -4)
4x + 6y = 180
------------------add
2y = 20
y = 20/2
y = 10 <===
x = 30
Any linear equation can be written as
y = mx+b
where m is the slope and b is the y intercept
m = 1/2 in this case. It represents the idea that the snow fell at a rate of 1/2 inch per hour. In other words, the snow level went up 1/2 an inch each time an hour passed by.
b = 8 is the y intercept. It's the starting amount of snow. We start off with 8 inches of snow already.
The info "snow fell for 9 hours" doesn't appear to be relevant here.