Question 618101
june is filling her gas tank after 10 seconds her gas has 5 gallons in it. after 25 seconds her gas has 9.5 gallons in it  .suppose the amount of gas in the tank depends lineraly on time . 

a ) write an equation describing the gallons of gas in the tang after s seconds.
4.5 gallons were added in 15 seconds --> 0.3 gallons/sec flow rate
@ t = 10, g = 5
10 sec*0.3 gal/sec --> 3 gallons less at t = 0 = 2 gallons
----------
g(t) = 2 + 0.3t
==========================
b ) how much gaswill be in the tank after 50 seconds
g(50) = 2 + 0.3*50 = 17 gallons 

c ) what is the y intercept of the equation you found ?
There is no y, it's g and t for gallons and time.
The g-intercept (at t=0) is 2.
-----------------
 What does this number mean in this problem
It's the # of gallons she had before adding any to the tank.