<span>а)1*а=а=верно при всех значениях а</span>
<span><span>б)0*н=4, н=4/0-на 0 делить нельзя, не имеет решения</span></span>
<span><span><span>в)(к-5)*9=0</span></span></span>
<span><span><span>к-5=0,9=0</span></span></span>
<span><span><span>к=0+5=0</span></span></span>
<span><span><span><span>г)3>12-в</span></span></span></span>
<span><span><span><span>3-12>-в</span></span></span></span>
<span><span><span><span>-9>-в</span></span></span></span>
<span><span><span><span>в>9</span></span></span></span>