Which function represents this graph? a. y=4x b. y=2x+3 c.y=1/2 x+3 d. y=2x-3

From the graph you can see that this function has a steep positive slope and a y-intercept of (0,3). That eliminates all answers but B.

The best way to work out something like this is to find out what ten percent is. The way in which you do this is to divide the price by 10. This gives you $36.90. Therefore, this is equal to ten percent. As you're looking for forty percent, you need ot mulitply the answer by four, and this gives you $147.60. You then have to subtract $147.60 from $369
$369-147.60= $221.40
I deleted my answer and put the correct one- sorry about that, my calculator seems to have a mind of its own :)