Answer: The height and width of the aquarium are 13 inches and 10 inches respectively .
Explanation:
Given : The volume of aquarium = 2730 cubic inches
Length of aquarium = 21 inches
Let x be the width of the aquarium,
then Height = x+3
We consider the shape of aquarium as cuboid.
Volume of Cuboid = Length x width x Height
Put values in the above formula , we get
![2730=(21)(x)(x+3)\\\\\Rightarrow\ 130=x^2+3x\\\\\Rightarrow\ x^2+3x-130=0\\\\\Rightarrow\ x^2+13x-10x-130=0\\\\\Rightarrow\ x(x+13)-10(x+13)=0\\\\\Rightarrow\(x+13)(x-10)=0\\\\\Rightarrow\ x=-13\ or\ x=10](https://img.qammunity.org/2021/formulas/mathematics/college/2e7fybel6t5tlddtfyeocsys3r7m4hcmup.png)
So , the width of aquarium =x= 10 inches ( width cannot be negative)
So height = 10+3=13 inches.
Hence, the height and width of the aquarium are 13 inches and 10 inches respectively .