determine how dilation affects the area of a pentagon when the sides of the pentagon are dilated by a scale factor less than 1

1 answer

When a pentagon (or any geometric shape) undergoes dilation by a scale factor, the change in area can be determined by the square of that scale factor.

If the sides of the pentagon are dilated by a scale factor \( k \) (where \( 0 < k < 1 \)), the following occurs:

  1. Linear Dimensions: Each linear dimension of the pentagon (such as the lengths of its sides) is multiplied by the scale factor \( k \).

  2. Area Calculation: The area of the original pentagon is affected by the square of the scale factor because area is a two-dimensional measurement. Therefore, if the original area of the pentagon is \( A \), the area \( A' \) of the dilated pentagon will be calculated as follows: \[ A' = k^2 \cdot A \]

Since \( k \) is a fraction (less than 1), \( k^2 \) will also be a fraction less than 1. This means:

  • The area of the dilated pentagon will be smaller than the original area.
  • Specifically, the new area will be \( k^2 \) times the original area, indicating a reduction in area.

In summary, when the sides of a pentagon are dilated by a scale factor less than 1, the area of the pentagon decreases, specifically by a factor of \( k^2 \).