he vertices of trapezoid EFGH are located at E (1, 1), F (3, 1), G (4, -2), and H (0, -2). After EFGH has been dilated with a scale factor of 3 about the origin, which two statements are true about the vertices of image E'F'G'H' ?

1 answer

To determine the coordinates of the dilated trapezoid EFGH after a dilation with a scale factor of 3 about the origin, we can use the formula for dilation of a point \( (x, y) \) about the origin:

\[ (x, y) \rightarrow (kx, ky) \]

where \( k \) is the scale factor.

Given the vertices of trapezoid EFGH:

  • E (1, 1)
  • F (3, 1)
  • G (4, -2)
  • H (0, -2)

Applying the dilation with a scale factor of 3:

  1. Vertex E: \[ E' = (3 \cdot 1, 3 \cdot 1) = (3, 3) \]

  2. Vertex F: \[ F' = (3 \cdot 3, 3 \cdot 1) = (9, 3) \]

  3. Vertex G: \[ G' = (3 \cdot 4, 3 \cdot -2) = (12, -6) \]

  4. Vertex H: \[ H' = (3 \cdot 0, 3 \cdot -2) = (0, -6) \]

Now we have the new vertices of the dilated trapezoid E'F'G'H':

  • E' (3, 3)
  • F' (9, 3)
  • G' (12, -6)
  • H' (0, -6)

Statements about the vertices of image E'F'G'H':

  1. The lengths of the bases of the trapezoid E'F'G'H' are proportional to the original trapezoid EFGH.

    • Since dilation maintains the shape but scales the distance, if EFGH had bases EF and GH, E'F' will be a scaled version of EF, and likewise for GH.
  2. The trapezoid E'F'G'H' is similar to trapezoid EFGH.

    • All corresponding angles are preserved, and the ratios of corresponding sides remain constant, which is a property of similar figures.

Therefore, the two true statements about the vertices of image E'F'G'H' are that their corresponding sides are proportional and the trapezoids are similar.