It appears that each company has a base charge for installation, which is the dollar value where each line begins at the y-axis. Both lines have the same slope and if you count, the cost is $75 per 5 linear feet.
It is -2. This is negative. For instance, if you had 3 candies and your mother took away 5, you would not only have 0 candies, but you would owe your mother 2. This is expressed as a negative number. Please mark Brainliest!!!