Odpowiedź :
Odpowiedź:
a) 9x + 7 = 9x - 11 /-7
9x = 9x -11 -7 /-9x
9x-9x = -18
0 ≠ -18
brak rozwiązań
b) 2(x+2) = 5(x-1)
2x +4 = 5x - 5 /-4
2x = 5x -5 -4 /-5x
2x-5x = -9
-3x = -9 /:-3
x = 3
c) 2(5x - 1) = 8
10x - 2 = 8 /+2
10x = 8+2
10x = 10 /:10
x = 1
a)
9x + 7 = 9x - 11
9x-9x=-11-7
0=-18
x∈∅
b)
2(x + 2) = 5(x - 1)
2x+4=5x-5
2x-5x=-5-4
-3x=-9 |:(-3)
x=3
c)
2(5x - 1)= 8 |:2
5x-1=4
5x=4+1
5x=5 |:5
x=1