Х-1 15\16=8 1\16+4 9\16-7 3\16
х-1 15\16=5 7\16
х=5 7\16+1 15\16
х= 6 22\16
х=7 6\16
х=7 3\8
Cos(π + β) = -cosβ
sin(π/2 - y) = cosy
1) <span>4x+7= -28 - x
4х+х=-28-7
5х=-35
х=-35:5
х=-7
2)</span><span>2(3 - 4x) - 5= 6 - 7(x+8)
6-8х-5=6-7х-56
-8х+7х=6-56-6+5
-х=-51
х=51</span>