15-х^2=6
х^2=15-6
х^2=9
х=3
15-3*3=15-9=6
Задача
35-7=28т угля вывезли
28:4=7 машин было выделено
<span>d+1/5=4/7+3/7</span>
<span>д+1/5=7/7</span>
<span>д=1-1/5</span>
<span>д=4/5</span>
<span>
</span>
<span><span>f+4/5=4/7+3/7</span></span>
<span><span>f+4/5=7/7</span></span>
<span><span>f=1-4/5</span></span>
<span><span>f=1/5</span></span>
<span><span>
</span></span>
<span><span><span>b+2/5=4/7+3/7</span></span></span>
<span><span><span>b+2/5=7/7</span></span></span>
<span><span><span>b=1-2/5</span></span></span>
<span><span><span>b=3/5</span></span></span>
42:6*8=56
1)42:6=7
2)7*8=56