б) <span>m-(3.5+m)= m - 3.5 - m = - 3.5</span>
<span>в) <span>-1,3+(х-4,8)=-7,1 </span></span>
<span><span>-1.3 + x - 4.8 = - 7.1</span></span>
<span><span>x = - 7/1 + 4.8 + 1.3</span></span>
<span><span>x = 0</span></span>
г) <span>9-(8 2//3-х)= 9 - 8 2/3 + x = 1/3 + x | x = - 1/3</span>
<span>д) <span>c-(a+c)=c - a - c = -a</span></span>
<span><span>e) <span> (m+n)-(n-m)= m + n - n + m = 2m </span></span></span>
Просто раскрываем скобки и выполняем действия :)