<span>-13+5х=3(9-5х),
-13+5х=27-15х,
5х+15х=27+13,
20х=40,
х=40:20,
х=2.
Ответ: 2.</span>
А). k<0, b<0 - 1). график
Б). k>0, b>0 - 2). график
B) k<0, b>0 - 3). график
(2a2-b)(2a-b)-2a2+5ab=4a3-2a2b+2ab+b2-2a2+5ab=4a3-2a3b+7ab-2a2+b2.
![y'=1- \frac{4}{ x^{2} } \\ y'=0 \\ 1- \frac{4}{ x^{2} } =0 \\ x=б2 ](https://tex.z-dn.net/?f=y%27%3D1-+%5Cfrac%7B4%7D%7B+x%5E%7B2%7D+%7D+%5C%5C+y%27%3D0+%5C%5C+1-+%5Cfrac%7B4%7D%7B+x%5E%7B2%7D+%7D+%3D0+%5C%5C+x%3D%D0%B12%0A)
![y(1)=1+ \frac{4}{1} =5 \\ y(2)=2+ \frac{4}{2} =4 \\ y(3)=3+ \frac{4}{3} =4 \frac{1}{3}](https://tex.z-dn.net/?f=y%281%29%3D1%2B+%5Cfrac%7B4%7D%7B1%7D+%3D5+%5C%5C+y%282%29%3D2%2B+%5Cfrac%7B4%7D%7B2%7D+%3D4+%5C%5C+y%283%29%3D3%2B+%5Cfrac%7B4%7D%7B3%7D+%3D4+%5Cfrac%7B1%7D%7B3%7D+)
Ответ: yнаиб=5 при x=1, yнаим=4 при x=2.