Please help i dont understand

9514 1404 393

  a = 74 cm

Step-by-step explanation:

The relationship between the apothem, side length, and area is usually expressed in the formula ...

  A = 1/2Pa

where P is the perimeter of the regular polygon. Here, P = 5s, so the area is ...

  A = (1/2)(5s)a

Solving for the apothem, a, we have ...

  a = 2A/(5s)

  a = 2(19887.5 cm^2)/(5(107.5 cm)) = (39775/537.5) cm

  a = 74 cm

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Additional comment

The integer result confirms the above approach you're intended to use with this problem.

The apothem can also be found from the side length directly (without regard to the area). In an n-sided regular polygon, ...

  a = (s/2)/tan(180°/n)

For s=107.5 and n=5, this is

  a = 107.5/(2·tan(36°)) ≈ 73.98

This problem is one of the better ones in that the apothem comes out about the same either way it is calculated. We have seen many (poorly-devised) math problems where using one formula gives vastly different results than those obtained from the other formula.

c.

step-by-step explanation:

she should of added 9^2 and 12^2. that is because it is a^2+b^2=c^2. c^2 is the hypotenuse and should always be bigger than the other two numbers. which is why she should of added 9 squared and 12 squared together instead of 15 squared.

x-150=475   x=625

step-by-step explanation:

if the bike after the sale ($150) is $475 then just simply add 150 to 475.