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Calculati nr nat x pentru care
a)8-(18-6):6=[8-3•(9-7)]•x
b)[(124+150-x):6]:31-2=0
c)128-[48+6•7-(x:3+15)]:3=104
Va rog frumos sa ma ajuti repede,Am mare nevoie,Dau fundita,Multumesc


Răspuns :

c)128 - [48+6•7-(x:3+15)]:3  = 104 ⇔  [48+6•7-(x:3+15)]:3 = 128 - 104 ⇔

⇔ [48+6•7-(x:3+15)]:3 = 24 |·3 ⇔ 48+6•7-(x:3+15) = 72 |-48 ⇔

⇔ 6•7-(x:3+15) = 24 ⇔ 42 = 24 + (x:3+15) |-24 ⇔ 18 =  (x:3+15) ⇔

⇔    x:3+15 = 18 |-15 ⇔ x:3 = 3 ⇔ x = 9 .