Find the slope of the line represented by the table

Use the function f(x) is graphed below. the graph of the function to find, f(6). -2 -1 1 2

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An internet company charges $8.95 per month for the first 3 months that it hosts your web site. then the company charges $11.95 per month for web hosting. how much money, in dollars, will the company charge for 8 months of web hosting?