<span>1)-0,8х-2,9=-2,9+5,8х</span>
<span>-0,8x-5,8x=2,9-2,9</span>
<span>-6,6x</span>
<span>x=6,6</span>
<span><span>2)1/3а-0,7=-3/5а-3,5</span></span>
<span><span>0,3a+0,6a=0,7-3,5</span></span>
<span><span>0,9a=-2,8</span></span>
<span><span>a=-3,1</span></span>
<span><span><span>3)-3(2у-4)=7у-(-у-2)</span></span></span>
<span><span><span>-6y+12=7y+y+2</span></span></span>
<span><span><span>-6y-8y=-12+2</span></span></span>
<span><span><span>-14y=10</span></span></span>
<span><span><span>y=-10/14=-5/7</span></span></span>
4)8-k 8k-1
----- = ----
4 5
8-k 8k-1
----- - ----- =0
4 5
40-5k-32k+4=0
-5k-32=-40-4
-37k=-44
k=44/37=1,18