−
3
y
−
5
x
3
+
6
+
2
−
4
y
+
5
y
+
6
x
3
−3y−5x
3
+6+2−4y+5y+6x
3

The polynomial 2x3 + 9x2 + 4x - 15 represents the volume in cubic feet of a rectangular holding tank at a fish hatchery. the depth of the tank is (x – 1) feet. the length is 13 feet.