11*-5-13у+16=0
-55-13y+16=0
-13y=-16-55
-13y=-71 умножаем на -1
13y=71
y=5.5
-х+4(7-х)=-7х+5
-х+28-4х=-7х+5
-х-4х+7х=5-28
2х=-23
х=-23/2
х=-11,5
<span>-4(х-10)=12(х-1)
-4х+40=12х-12
-4х-12х=-12-40
-16х=-52
х=-52:(-16)
х=3.25
</span><span>-х+2=х-6
-х-х=х-6
-2х=-8
х=-8:(-2)
х=4</span>