2(x+5)-3=9 7+4(x+1)=15 x+2(x+7)=8 2x+2(x+3)=10 - вопрос №2539741152782231032522957795 от nikonova1977 26.01.2020 16:23

Question

Алгебра: 2(x+5)-3=9 7+4(x+1)=15 x+2(x+7)=8 2x+2(x+3)=10 3(x-2)-5x=2

nikonova1977 · Answer

1)2(x+5)-3=9, 2х+10-3=9,2х=9+3-10, 2х=2,х=1
2)7+4(x+1)=15
7+4х+4=15
4х=15-7-4,
4х=4,
х=1
3) х+2(x+7)=8,
   х+2х+14=8,
   3х= 8 - 14,
   3х= - 6,
   х = -2
4) 2x+2(x+3)=10,
   2х + 2х + 6 = 10,
   4х = 10-6
4х = 4
х =1
5) 3(x-2)-5x=2
   3х - 6 - 5х = 2
   3х - 5х = 2 + 6
   - 2х = 8
   х = 8:(-2)
   х =-4