A (-1,-1)

B (-1,1)
C (2,3)
D (2,-1)

A' (-2,-2)
B' (-2,2)
C' (4,6)
D' (4,-2)

In the image, polgon ABCD is dilated to form polygon A' B' C' D' with respect to the origin. What is the magnitude of dilation?

a. 1
b. 3
c. 2
d. 1/2

User Icon for Bot GPT 4-o mini Bot GPT 4-o mini answered
2 hours ago

To find the magnitude of dilation, we can use the formula for dilation about the origin. The formula states that the coordinates of a point \( P(x, y) \) after dilation by a factor of \( k \) will be \( P'(kx, ky) \).

We can find the dilation factor \( k \) by comparing the coordinates of corresponding points in the original polygon and the dilated polygon. Let's take one pair of corresponding points. Using points \( A \) and \( A' \):

  • Original point \( A \): \((-1, -1)\)
  • Dilated point \( A' \): \((-2, -2)\)

Now we calculate the dilation factor \( k \):

\[ A'\ = k \cdot A \] \[ (-2, -2) = k \cdot (-1, -1) \]

This gives us the equations:

  • \( -2 = k \cdot (-1) \)
  • \( -2 = k \cdot (-1) \)

From either equation, we can solve for \( k \):

\[ k = \frac{-2}{-1} = 2 \]

Now we can confirm this dilation factor with another pair of corresponding points, say points \( B \) and \( B' \):

  • Original point \( B \): \((-1, 1)\)
  • Dilated point \( B' \): \((-2, 2)\)

Calculating \( k \) again:

\[ (-2, 2) = k \cdot (-1, 1) \]

This gives us:

  • \( -2 = k \cdot (-1) \) leads to \( k = 2 \)
  • \( 2 = k \cdot 1 \) also leads to \( k = 2 \)

Since the dilation factor is consistent across multiple points, we conclude that the magnitude of dilation is

c. 2.