We can assume that the shape is a rectangular prism by the given dimensions
Volume of a rectangular prism Volume = Area of Base × Height of prism = Length × Width × Height of prism Substitute! 168 = L × 7 × 3 168 = L × 21 Divide 21 on either sides to isolate L
[tex] \frac{168}{21} [/tex] = [tex] \frac{L*21}{21} [/tex] 21 and 21 cancels out
