Полная площадь поверхности аквариума: <span>S</span><em>=</em><span> </span><span>S</span>a<em>+2(</em><span>S</span>b<em>+</em><span>S</span>c<em>)=</em><span> </span><span>a*b</span><em>+</em><span> 2(b*c</span><em>+</em><span> a*c</span>)=50*25+2(25*30+50*30)=1250+2(750+1500)=1250+2*2250=1250+4500=5750 см²
1)13х=22+4; 13х=26; х=26:13; х=2; 2)11х=33; х=33:11; х=3
29:2 3\13-13.6+1=0.4
1)29:2 3\13=29*13\29=13
2)13-13.6=-0.6
3)-0.6+1=0.4