<span>1)(2x-3)(x+5)-2=11-(x-4)^2
2x^2-3x+10x-15=11-x^2+8x-16
</span><span>2x^2-3x+10x-15-11+x^2-8x+16=0
3x^2-x-10=0
</span><span>2)(5x-1)(5x+1)+20x^2=7x-3
</span><span>25x^2-1+20x^2-7x+3=0
</span>45x^2+-7x+2=0<span>
</span><span>3)(8-x)(8+x)+(1-4x)^2=12x^2+1
</span><span>64-x^2+1-8x+16x^2-12x^2-1=0
</span><span>13x^2-8x+64=0
</span><span>
16</span>
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= <u>51+17</u>
13,6 = 5
х2 = <u>51-17
</u> 13,6 = 2,5
Ответ: [5;+∞)
Смотри ответ во вложении.