<span>54-x=27</span>
<span>х=54-27</span>
<span>х=27</span>
<span>54-27=27</span>
<span><span>x-33=39</span></span>
<span><span>х=39+33</span></span>
<span><span>х=72</span></span>
<span><span>72-33=39</span></span>
<span><span><span>28+x=34</span></span></span>
<span><span><span>х=34-28</span></span></span>
<span><span><span>х=6</span></span></span>
<span><span><span>28+6=34</span></span></span>
(х-6/13)*13=(5х+6)*0,8
13х-6=4х+4,8
13х-4х=4,8+6
9х=10,8
х=1,2
1+2+3=6(ч)- вместе
72÷6=12(стр/ч)- каждая
12×1=12(стр)- первая
12×2=24(стр)- вторая
12×3=36(стр)- третья
29*9=(30-1)*9
29*9=29*9
261=261
1=1