А)12-3(7-X)=9-4(X+5) . б)4(2х-5)-8=-7+5(4-9х) в) 3(7-8х)+2(х-1)=-8(3+х)+2(4-х)...

Question

А)12-3(7-X)=9-4(X+5) . б)4(2х-5)-8=-7+5(4-9х) в) 3(7-8х)+2(х-1)=-8(3+х)+2(4-х) г)7(6-2У)-10(1У)=-2(У+1)+4(3У-5)

Answer 1

А)
12-3(7-х)=9-4(х+5)
12-21+3х=9-4х-20
3х+4х=21-12+9-20
7х=-2
х=-2:7
х=-2/7
Ответ: -2/7.
б)
4(2х-5)-8=-7+5(4-9х)
8х-20-8=-7+20-45х
8х+45х=20+8+20-7
53х=41
х=41:53
х=41/53
Ответ: 41/53.
в)
3(7-8х)+2(х+1)=-8(3+х)+2(4-х)
21-24х+2х+2=-24-8х+8-2х
23-26х=-16-10х
-26х+10х=-16-23
-16х=-39
х=39:16
х=2 7/16
Ответ: 2 7/16.