Answer:
They did make a mistake because you have to subtract the 7 not add it to the 5 because of the five now being a positive and the 7 being a negative. So if i am reading it right they made the mistake at step 2.
Step-by-step explanation:
3 - (-5) - 7
3 + 5 - 7
3 - 2
1
yes he did make a mistake
he was supposed to add the 3 and the 5 together first and then subtract and if that's not the answer then he was to supposed to add a -2
