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A building engineer analyzes a concrete column with a circular cross section. The circumference of the column is 18pi meters.
What is the area A of the cross section of the column?
Give your answer in terms of pi.
A = m spuared

Respuesta :

Answer:

  • 81π m²

Step-by-step explanation:

Circumference formula: C = 2πr

Compare with given value and determine the radius:

  • 2πr = 18π
  • r = 18π/2π
  • r = 9 m

Find the area of the cross-section.

Area formula: A = πr²

Area: A = 9²*π = 81π m²

Find radius

  • C/2π
  • 18π/2π
  • 9m

So.area

  • πr²
  • 9²π
  • 81πm²