9а^2-16 = (3a-4)(3a+4)
x^2+18x^2+81x= 19x^2+81x=x(19x+81)
1^127=1
0^127=0
...................
X+ (5x-3)/(x-3)≥0
(x²+2x-3)/(x-3)≥0
(x+3)(x-1)/(x-3)≥0
x=-3 x=1 x=3
_ + _ +
-----------------------------------------------------------
-3 1 3
x∈[-3;1] U (3;∞)
Неправильно;2х > 70, x < 100 <span>x > 5 </span>
Правильно;3x ≥ 24, x ≥ 10