We have a prism with a volume of 16y⁴ + 16y³ + 48y² cubic units.
Its volume is equal to the area of its base times its height.
Of course, for those to be the base area and height of this prism, they would have to multiply to 16y⁴ + 16y³ + 48y² cubic units.
Let's test each of these answers to see which gives us the correct volume.
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a base area of 4y square units and height of 4y² + 4y + 12 units
We find the volume by multiplying the base area by the height...
4y(4y² + 4y + 12)
Distribute the 4y to each term inside the parentheses.
16y³ + 16y² + 48y
This is not the right volume, so these can not be dimensions of our prism.
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a base area of 8y² square units and height of y² + 2y + 4 units
We find the volume by multiplying the base area by the height...
8y²(y² + 2y + 4)
Distribute the 8y² to each term inside the parentheses.
8y⁴ + 16y³ + 32y²
This is not the right volume, so these can not be dimensions of our prism.
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a base area of 12y square units and height of 4y² + 4y + 36 units
We find the volume by multiplying the base area by the height...
12y(4y² + 4y + 36)
Distribute the 12y to each term inside the parentheses.
48y³ + 48y² + 432y
This is not the right volume, so these can not be dimensions of our prism.
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a base area of 16y² square units and height of y² + y + 3 units
We find the volume by multiplying the base area by the height...
16y²(y² + y + 3)
Distribute the 16y² to each term inside the parentheses.
16y⁴ + 16y³ + 48y²
The volume fits, so these could be the base area and height of our prism.
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D. a base area of 16y² square units and height of y² + y + 3 units
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