5x + 5 = 20 /-5
5x = 15 /:5
x = 3
-3x - 4 = 5 /+4
-3x = 9 /:(-3)
x = -3
3 - x = -2 /-3
-x = -5 /*(-1)
x = 5
2 - 2x = 5 /-2
-2x = 3 /:(-2)
x = -1,5
Odpowiedź:
5x+5=20
5x=20-5
5x=15/5
x=3
-3x-4=5
-3x=5+4
-3x=9/(-3)
x=-3
3-x=-2
-x=-2-3
-x=-5/(-x)
x=5
2-2x=5
-2x=5-2
-2x=3/(-2)
x=-3/2=-11/2