Răspuns :
(2x +1): 3 = 7
2x + 1 = 3 x 7
2x + 1 = 21
2 X = 21 - 1
2X = 20
X = 20 :2
X= 10
10 : ( 5X+2) = 5
5X + 2 = 10 : 5
5X + 2 = 2
5X = 2-2
5X = 0
X = 5 x 0
x=0
2x + 1 = 3 x 7
2x + 1 = 21
2 X = 21 - 1
2X = 20
X = 20 :2
X= 10
10 : ( 5X+2) = 5
5X + 2 = 10 : 5
5X + 2 = 2
5X = 2-2
5X = 0
X = 5 x 0
x=0