Question

The right pengtagonal prism has a height of of 14 units.

A pentagonal prism has a perpendicular distance of 14 units between the bases. An apothem has a length of 4 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

Answer 1

30

Explanation:

because i done took it

Answer 2

30 units

Explanation:

The volume is given by ...

V = Bh

Filling in the given numbers, we can find the area of the base (B) to be ...

840 = B(14)

840/14 = B = 60

The area of the base is given by the formula ...

B = (1/2)Pa

where P is the perimeter and a is the apothem. Filling in the numbers we know, we have ...

60 = (1/2)P(4)

30 = P . . . . . . divide by 2

The perimeter of the base is 30 units.