Answer:
addition
Step-by-step explanation:
32(d/2 - 5) = 224
divide both side by 32
d/2 - 5 = 224/32
d/4 - 5 = 7
multiply both sides by 4
d - 20 = 28
lastly, add 20 to both sides
d = 28 + 20
d = 48
therefore, the last step is addition