A pet shop had 8 identical fish tanks in the shape of rectangular prisms. The width and height of each tank was (x - 7) inches and the length was 8 inches more than its width. The expression below shows the maximum amount of water which all the tanks together can hold.
8(x + 1)(x - 7)2

What does the factor (x - 7)2 represent?

The total base area of all the tanks
The total surface area of each tank
The area of the rectangular base of each tank
The area of a square shaped side of the tank

Question

A pet shop had 8 identical fish tanks in the shape of rectangular prisms. The width and height of each tank was (x - 7) inches and the length was 8 inches more than its width. The expression below shows the maximum amount of water which all the tanks together can hold.
8(x + 1)(x - 7)2

What does the factor (x - 7)2 represent? 

 	
	The total base area of all the tanks
	The total surface area of each tank
	The area of the rectangular base of each tank
	The area of a square shaped side of the tank

mrnood · Answer

the total that EIGHT identical tanks can hold is

8 times (x + 1)(x - 7)^2

To start with - can you write write the volume of ONE tank?...

anonymous · Answer

(x+1)(x-7)^2

mrnood · Answer

OK good

now - a 'rectangular prism is just a fancy name for a cuboid

the voloume of a cuboid is 

l times w times h

but it tell you the the width and the height are both (x-7)

so how could you write l times w times h using that expression (x-7)??

mrnood · Answer

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