Question

What will be the y - coordinate of B’ if AB is dilated by a factor of, centered at the origin?

Answer 1

Answer: 4/5 (choice B)

Reason:

B is located at (10,2)

Multiply each coordinate by the scale factor 2/5

• 10*(2/5) = 20/5 = 4 is the x coordinate of B'
• 2*(2/5) = 4/5 is the y coordinate of B'

This trick only works if the center of dilation is the origin.