(3-5x)^2-(3x-2)(5x+1)=9-30x+25x^2-(15x^2+3x-10x-2)=9-30x+25x^2-15x^2+7x+2=10x^2-23x+11;
A) 100x-5=100
100x=105
x=105/100=1,05
Б) 5^2=3х-2
25=3х-2
3х=27
х=9