Odpowiedź:
13x +5 = 7x -2 /-5
13x = 7x -7 /-7x
6x= -7 /:6
x = - 7/6
-x +28 +2x =13 /grupujemy
x +28 = 13 /-28
x = -15
18-12x - 3 =17-2x /grupujemy
15 - 12x = 17-2x /+12x
15 = 10x + 17 /-17
10x = -2 /:10
x = -1/5
3x + 8x =12
11x = 12 /:11
x = 12/11 czyli 1 i 1/11
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4
2x - 5 =1 /+5
2x = 6 /:2
x = 3
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3
-2 razy 5x =7 - 3x
-10x = 7 - 3x /+3x
-7x = 7 /*(-7)
x = -1