Question

Rezolvați ecuațiile:
2×{27-2×[3x-(42:6-3×2)]+3}=40
2)125+5×[3×(300-14×21)+1]+x=221

Answer 1

1)
2×{27-2×[3x-(42:6-3×2)]+3}=40
2×{27-2×[3x-(7-6)]+3}=40
2×[27-2×(3x-1)+3]=40
2×(27-6x+2+3)=40
2×(32-6x)=40
32-6x=40:2
32-6x=20
6x=32-20
6x=12
x=12:6
x=2

2)
125+5×[3×(300-14×21)+1]+x=221
125+5×[3×(300-294)+1]+x=221
125+5×(3×6+1)+x=221
125+5×19+x=221
125+95+x=221
220+x=221
x=221-220
x=1