661. -6(9-5x)=9x+9<span>
</span>-54+30x=9x<span>+9
30</span>x-9x<span>=9+54
21</span>x<span>=63
</span>x=3.
666. 4+5(-3x<span>+7)=-9
4-15</span>x<span>+35=-9
-15</span>x<span>=-9-4-35
-15</span>x<span>=-48
</span>x=3,2.
667. 5+10(-10x<span>-9)=-3
5-100</span>x<span>-90=-3
-100</span>x<span>=-3-5+90
-100</span>x<span>=82
</span>x=-0,82.
673.1-6(2x<span>-3)=-2
1-12</span>x<span>+18=-2
-12</span>x<span>=-2-1-18
-12</span>x<span>=-21
</span>x=1,75
<span>674. 10+9(-10-9x)=8-x
10-90-81x=8-x
-81x+x=8-10+90
80x=88
x=1,1</span>
<span>675. -1+8(7-6x)=2x=6
-1+56-48x=2[+6
-48x-2x=6-56+1
-50x=-49
x=</span>0,98
<span>676. -2+3(1+2x)=-2x+3
-2+3+6x=-2x+3
6x+2x=3-3+2
8x=2
x=0,25</span>