<span>а)4x+12,3-(-7,2)=20-x </span>
<span>4x+12,3+7,2=20-x</span>
<span>4х+х=20-12,3-7,2</span>
<span>5х=0,5</span>
<span>х=0,1 </span>
<span>б)0,003-х=0,023-1 </span>
<span>-х=0,023-1-0,003</span>
<span>-х=-0,98</span>
<span>х=0,98</span>
<span>в)7*(3х-1)=5*(х-3)</span>
<span>21х-7=5х-15</span>
<span>21х-5х=7-15</span>
<span>16х=-8</span>
<span>х=-0,5</span>
<span>г)-1/2+4х-х=2х-5,1 </span>
<span>-1/2+3х=2х-5,1</span>
<span>3х-2х=1/2-5,1</span>
<span>х=0,5-5,1</span>
<span>х=-4,6</span>