Step-by-step explanation:
If y was directly proportional to x, the graph of y against x would pass through the origin (O).
Since the graph above does not show this, y is not directly proportional to x.
Answer:
7 x 7 x 8 = 392
15 x 7 x 7(14 - 7) = 735
735 + 392 = 1,127 in^3 is your answer.
Let's split the figure: