19.2k views
2 votes
Need help with dilations mix

1 Answer

5 votes

When you add/subtract values to the coordinates of a figure, its size doesn't change, you only move it to another location.

When you multiply the coordinates of a figure, you enlarge it, i.e. create a bigger figure proportional to the original one.

When you divide the coordinates of a figure, you reduce its size.

Since the figure was dilated and not moved, option F is incorrect.

To determine how much it was dilated select any point from the pre image and image and compare them.

For example

G (-2,1)

G'(-5,2.5)

To determine the coefficient used for the dilation divide the x-coordinate of the image point by the x-coordinate of the preimage point:


(X_(G^(\prime)))/(X_G)=(-5)/(-2)=(5)/(2)

Now do the same to determine the coefficient used in the Y-coordinates:


(Y_(G^(\prime)))/(Y_G)=(2.5)/(1)=2.5

2.5 expressed in fractions is 5/2

So the dilation made was (X,Y)→(2/5X,2/5Y)

The correct answer is E.

User Spacenick
by
8.5k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories