Answer:2, -2, 6 or -6
Explanation:
Given,
The location of Ann's house in the number line = 0,
∵ Ben lives 4 blocks from Ann.
So, the possible location of Ben's house = 4 ( right of ann's house ) or - 4 ( left of ann's house )
Now, Carl lives 2 blocks from Ben,
So, the possible location of Carl's house
Case 1 : If Ben's house location is 4 = 2 ( left of ben's house ) or 6 ( right of ben's house )
Case 2 : If Ben's house location is -4 = -2 ( right of ben's house ) or -6 ( left of ben's house )