A student solved this problem. Use the drop-down menus to justify steps 1 and 3.

8 + [4(16 + 23)]
Step 1: 8 + [4(16) + 4(23)]
Step 2: 8 + (64 + 92)
Step 3: 8 + (92 + 64)
Step 4: (8 + 92) + 64
Step 5: 100 + 64
Step 6: 164