2(-1.6-1/2x1/6)-(-1.2-7x1/3)=3.2-(-53/15)=3.2+53/15=17/3
<span>x+y-(x^3+y^3)=x+y-(x+y)*(x^2-x*y+y^2)=(x+y)*(-x^2+x*y-y^2+1)
вроде как то так</span>
<span>7(0,3x-2)-3(0,7x+3)=3
2.1х-14-2.1х-9=3
-23=3
</span><span>1,3(x-0,7)-0,12(x+10)=3
</span>1.3х-0.91-0.12х-1.2=3
1.18х-2.11=3
1.18х=3+2.11
1.18х=5.11
х=5.11:1.18
х=511/100:118/100
х=511/100*100/118
х=511*1/118
х=511/118
1) (6х²-5х+9)-(3х²+х-7)=6х²-5х+9-3х²-х+7=6х²-3х²-5х-х+9+7=3х²-6х+16;
2) (5а²-2а-3)-(2а²+2а-5)=5а²-2а-3-2а²-2а+5=5а²-2а²-2а-2а-3+5=3а²-4а+2;
3) (9у²-5у+7)-(3у²+2у-1)=9у²-5у+7-3у²-2у+1=9у²-3у²-5у-2у+7+1=6у²-7у+8;
4) (7в²-4в+2)-(5в²-3в+7)=7в²-4в+3-5в²+3в-7=7в²-5в²-4в+3в+2-7=2в²-в-5;