1)1 дм2 35 см2 =100 см2 +35 см2=135 см2.
4y+15=6y+17
-6y+4y=17-15
-2y=2
y=2:(-2)
y=-1
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<span>4(4+X)=28
4+x=28:4
4+x=7
x=7-4
x=3</span>
<span>-4(3,5x-4)-(7-2,1x)+5(0,3x-5)=-14х+16-7+2,1х+1,5х-25=-10,4х-16
Вычисляем при х=-10/27:
-10,4х*(-10/27)-16=
1)-10,4х*(-10/27)=-104/10*-10/27=104/27
2)104/27-16=(104-16*27)/27=(104-432)/27=-328/27=-12 4/27</span>