[tex]\it 1)\ \ A(2,\ -5)\inGf \Rightarrow f(2)=-5 \Rightarrow -2m\cdot2+3=-5 \Rightarrow -4m=-8 \Rightarrow m=2\\ \\ \\ 2)\ \ A(x,\ -x)\in Gf \Rightarrow f(x)=-x \Rightarrow 3x-2=-x \Rightarrow 4x=2 \Rightarrow x=\dfrac{1}{2}\\ \\ \\ 3)\ \ A(0,\ y)\in Gf \Rightarrow y=f(0)=-\dfrac{1}{3}[/tex]
[tex]\it 4)\ \ \ A(x,\ x)\in Gf \Rightarrow 4x-3=x \Rightarrow 3x=3 \Rightarrow x=1[/tex]
