Răspuns :
[tex](x-2)^2-(x+1)^2=x-4\\
x^2-4x+4-(x^2+2x+1)=x-4\\
x^2-4x+4-x^2-2x-1=x-4\\
-6x+3=x-4\\
-6x-x=-4-3\\
-7x=-7 ~~|*(-1)\\
7x=7\\
x= \frac{7}{7} \\
\boxed{x=1}[/tex]
=x²-4x+4 - (x²+2x+1)=x-4
=x²-4x+4-x²-2x-1=x-4
=-6x+3=x-4
=-6x-x=-7
=-7x=-7
x=7/7 =1
=x²-4x+4-x²-2x-1=x-4
=-6x+3=x-4
=-6x-x=-7
=-7x=-7
x=7/7 =1
