Answer:
length of image of AB is 4 inches.
Step-by-step explanation:
Scale factor(k) is defined as the ratio of image to the pre-image.
i.e,

as per the statement:
The length of AB is 10 inches. A dilation with a scale factor of 
⇒
and Length of pre-image AB = 10 inches.
by definition of scale factor:

Substitute the given values we have;

Simplify:
inches.
Therefore, the length of image AB is 4 inches.