To graph this function, form ordered pairs from the chart. Because the x-axis is denoted to Radius and the y-axis to Area, we will want to graph the radius and corresponding area. Remember, x-coordinates always are graphed first, then the y-coordinate to plot a point.
A.) From the table, we can create the following ordered pairs in the form (x, y):
(1, 3) (2, 12) (3, 27) (4, 48) (5, 75)
Simply start at 0 and move left or right in the x-axis the amount of units the fist value says. Then, from that position, move up or down along the y-axis the value of the second coordinate. For example, in the pair (1, 3), you will move 1 unit right (+), then 3 units up from that position and plot the point. The point should be 1 space to the right and 3 spaces up from there.
B.) This graph is a function because it passes the vertical line test, meaning no x-value leads to two y-values. Every domain value is paired to exactly one range value.