Răspuns :
a -3750+3500-375+890=7000
a-3750+3500-375=7000-890
a-3750+3500-375=6110
a-3750+3500=6110+375
a-3750+3500=6485
a-3750=6485-3500
a-3750=2985
a=2985+3750
a=6735
x-3750+3500-375+890=7000. x-3750+3500-375=7000-890. x-3750+3500-375=6110. x-3750+3500=6110+375. x-3750+3500=6485. x-3750=6485-3500. x-3750=2985. x= 2985+3750. x=6735