4-3a/5-2b+5(a-10)/2b-5
4-3a/-(2b-5)+5a-50/2b-5
4+3a/2b-5+5a-50/2b-5
4(2b-5)+3a+5a-50/2b-5
8b-20+3a+5a-50/2b-5
8b-70+8a/2b-5
<span>18sin174 * cos174 = 9 sin2*174 = 9sin348</span>
<span> 9sin348</span>
<span><span>------------------------- = 9</span>
<span> SIN 348</span></span>
<span>10x-5=6(8x+3)-5x</span>
<span>10х-5=48х+18-5х</span>
<span>11х-43х=18+5</span>
<span>-33х=23</span>
<span>х=-23/33</span>
<span>
</span>
<span><span>30+5*(3-1)=35-25-здесь нет неизвестного???</span></span>
<span><span>20+15-5=10</span></span>
<span>-10(3-4x)+51=7(5x+3)</span>
<span>-30+40х+51=35х+21</span>
<span>40х-35х=21+30-51</span>
<span>5х=0</span>
<span>х=0</span>
<span>
</span>
<span><span>1,2(a+7)-1,8=1,2а+8,4-1,8=6,6+1,2а</span></span>
Ответ:
Приведение дробей к общему знаменателю.