Answer:
642
Step-by-step explanation:
639 -127 = x -130
x = 639 -127 +130 = 639 +3 = 642
use inverse operations
first find the difference of 639 and 127 to get 512
then using inverse operations add 512 to 130 to get 642
check by subtracting 642 by 130 to get 512
