5=1+1+1+1+1
60=10+10+10+10+10+10
200=100+100
265=100+100+10+10+10+10+10+10+1+1+1+1+1
220/100= 11/5= 2 1/5 (или 2,2)
(х+71,2)-37,6=95,61
х+71,2=133,21
х=62,01
Применены : основное тригонометрическое тождество, определение котангенса
<span>-7+..3.= -4 </span>
<span><span>-7+(-3)= -10</span></span>
<span><span><span>7+(-3)=4</span></span></span>
<span><span><span><span>(-9)+8=-1</span></span></span></span>
<span><span><span><span><span>(-9)+(-8) = -17</span></span></span></span></span>
<span><span><span><span><span><span>9+(-8)=1</span></span></span></span></span></span>
<span><span><span><span><span><span><span>9+(-9)=0</span></span></span></span></span></span></span>
<span><span><span><span><span><span><span><span>(-11)+11=0</span></span></span></span></span></span></span></span>
<span><span><span><span><span><span><span><span><span>-12+12=0 </span></span></span></span></span></span></span></span></span>