![image](https://tex.z-dn.net/?f=%282x%2B9%29%5E3+%3E+0)
0" alt="(2x+9)^3 > 0" align="absmiddle" class="latex-formula">
![image](https://tex.z-dn.net/?f=%282%28x%2B4%2C5%29%29%5E3+%3E+0)
0" alt="(2(x+4,5))^3 > 0" align="absmiddle" class="latex-formula">
![image](https://tex.z-dn.net/?f=8%28x%2B4%2C5%29%5E3+%3E+0)
0" alt="8(x+4,5)^3 > 0" align="absmiddle" class="latex-formula">
![image](https://tex.z-dn.net/?f=%28x%2B4%2C5%29%5E3+%3E+0)
0" alt="(x+4,5)^3 > 0" align="absmiddle" class="latex-formula">
Отмечаем на прямой ОХ точку x=-4,5 и методом интервалов (см.рисунок ) получаем ответ