Answer:
Jillian has made an error in steps 4.
Step-by-step explanation:
Given : Jillian is using integer tiles to add 7 + (-2).
To find : Jillian has made an error . In which steps does it occur.
Solution : We have given integer tiles to add 7 + (-2).
Step 1 : Jillian take the + 7 tiles , that is correct
Step 2 : Now , Jillian take another - 2 tile , that is also correct.
Step 3 : In this + 2 tiles cancel the -2 tile from +7 tiles.
Step 4 : Now he get 2 that is wrong because from the step 3 we get + 5 tile after canceling + 2 tiles from + 7.
Therefore, Jillian has made an error in steps 4.