C(t) = $2t + $8
This tells us that the basic cost of the pizza is $8, with no toppings, and that each topping costs an additional $2.
To graph this, plot a dot at (0,$8). Now move y our pencil point 1 unit to the right and then 2 units up. Plot a dot at this new location. Now draw a straight line connection (0, $8) and this new location (which is (1, $10) ).
There are 72 green pens.
There is 9 times as many white pens from 2 to 18, so there has to be 9 times as many green pens because of the ratio. 9 times 8 is 72.
