Ответ:
B)x∈(2.3;+∞)
Г)x∈(-∞;-7)∪(7;+∞)
Объяснение:
2.3x|:x\\x>2.3" alt="x^2>2.3x|:x\\x>2.3" align="absmiddle" class="latex-formula">
x∈(2.3;+∞)
5(4-x)\\x^2-5x-29>20-5x\\x^2-5x-29-20+5x>0\\x^2-49>0\\x^2>49\\" alt="x(x-5)-29>5(4-x)\\x^2-5x-29>20-5x\\x^2-5x-29-20+5x>0\\x^2-49>0\\x^2>49\\" align="absmiddle" class="latex-formula">
x>±7
+ - +
-------o------o-------
-7 7
x∈(-∞;-7)∪(7;+∞)