The right pengtagonal prism has a height of of 14 units. The volume of the prism is 840 cubic units. What is the perimeter of the base? 12 units 15 units 21 units 30 units

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Answer:

Option D is correct.

Step-by-step explanation:

Height of prism = 14 units

Volume of prism = 840 cubic units

Perimeter of base = ?

Volume of Prism = Base Area * Height

840 = Base Area * 14

=>Base Area = 840/ 14

Base Area = 60 square unit.

Now Area of pentagon:

[tex]Area=\frac{a^2}{4}\sqrt{5(5+2\sqrt{5}}[/tex]

We need to find a, where Area = 60

[tex]60=\frac{a^2}{4}*6.88\\60=a^2*1.72\\=>a^2=60/1.72\\=>a^2=34.88\\=>a=\sqrt{34.88}\\ a=5.91[/tex]

The pentagon has 5 sides.

So, perimeter of base = 5*a

perimeter of base = 5* 5.91

perimeter of base = 29.55 ≈ 30 units

So, Option D is correct.

Answer:

D is correct

Step-by-step explanation:

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