Students in Mr. Jackson’s class are simplifying an expression written on the board:
-12p-5n+8n+20p
Amal simplified the expression to be 8p+3n , and Andre simplified the expression to be -32p-13n
Mr. Jackson saw a few different answers around the classroom, so he gave the students a hint on the board, writing:
-12p-5n+20p
-12p+2op-5n+8n
(-12+20)p+(-5+8)n
What did Mr. Jackson do in each step he wrote on the board?