Исходные не пишу
(m-n)(2m+1)
4p(p+1)+(p+1)=(p+1)(4p+1)
a(x-c)-b(x-c)=(x-c)(a-b)
a(b+c)+d(b+c)=(b+c)(a+d)
2 -(x-4)/(x+5) ≤ 0;
(2(x+5) -(x-4))/(x+5)≤ 0;
(x + 14)*(x + 5) ≤ 0;
+ - +
---------------------- - 14 ----------------- - 4 ----------------------
x ∈ [ -14 ; - 5 ].