1. 4
2. a=-3, b=1, c=7
3. 2
4. -9
{6x-3≥3
{-5x≤-10
6x-3≥3
6x≥3+3
6x≥6
x≥6 : 6
х≥1
-5х≤-10
х≥ -10 : (-5)
х≥2
\\\\\\\\\\\\\\\\\\\\\\\\\\
--------- 1 --------- 2 ----------
\\\\\\\\\\\\\\\
x≥2 или х∈[2; +∞)
2√9-√64= 2*3-8= 6-8= -2
1/9√0,81 -1= 1/9*0,9-1= 0,1-1= -0,9