(5x-3)^2+(12x+5)^2 ≤ (7-13x)^2+34x^2+17x+410? - вопрос №37992395321252713234217410 от marinastolarova 21.07.2020 05:05

Question

Алгебра: (5x-3)^2+(12x+5)^2 ≤ (7-13x)^2+34x^2+17x+410?

marinastolarova · Answer

25х²-30х+9+144х²+120х+25≤49-182х+169х²+34х²+17х+410
169х²+90х+34≤459-165х+203х²
-34х²+255х-425≤0 I ÷(-5)
6,8х²-51х+85≥0
D= 2601 - 2312 = 289
х1= 51+17
13,6 = 5

х2 = 51-17
13,6 = 2,5

ответ: [5;+∞)