Răspuns :
2 ( 3 x - 1 ) = 10 l : 2
3 x - 1 = 5
3 x = 5 + 1
3 x = 6 ⇒ x = 6 : 3 ⇒ x = 2
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3 ( 2 x - 1 ) = 30 l : 3
2 x - 1 = 10
2 x = 11 ⇒ x = 11 / 2 = 5,5
Obs: E neclara ecuatia : 2x1 - 1
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5 ( x + 3 ) = 45 l : 5
x + 3 = 45 : 5
x = 9 - 3
x = 6
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54 ( 2 x - 4 ) = 27 l : 27
2 ( 2 x - 4 ) = 1
4 x - 8 = 1
4 x = 1 + 8
4 x = 9
x = 9 / 4 ⇒ x = 2,25