<span> 20 007-Х=20 000</span>
<span>x=20007-20000</span>
<span>x=7</span>
<span><span> Х-900=1 000</span></span>
<span><span>x=1000+900</span></span>
<span><span>x=1900</span></span>
<span><span><span> Х+200=3 200</span></span></span>
<span><span><span>x=3200-200</span></span></span>
<span><span><span>x=3000</span></span></span>
<span><span><span><span>300+Х=5 400</span></span></span></span>
<span><span><span><span>x=5400-300</span></span></span></span>
<span><span><span><span>x=5100</span></span></span></span>
<span><span><span>
</span></span></span>
<span><span>
</span></span>
<span><span>
</span></span>
<span><span>
</span></span>