[tex]f:\Bbb{R}\rightarrow \Bbb{R},\:\:f(x)=ax+5[/tex]
[tex]A(3, -1)\in G_f\implies f(3)=-1[/tex]
[tex]a\cdot 3+5=-1\implies a\cdot 3=-6\implies \boxed{a=-2}[/tex]
Prin urmare, [tex]f(x)=-2x+5\:\:(\forall)\: x\in\Bbb{R}.[/tex]
[tex]\text{Fie }\:G_f\:\cap\:Ox=\{A\}\implies y=0\implies -2x+5=0\\-2x=-5\implies x=\frac{5}{2}\implies\boxed{A(\frac{5}{2}, 0)}[/tex]
[tex]\text{Fie }\:G_f\:\cap\:Oy=\{B\}\implies x=0\implies y=f(0)=5\implies \boxed{B(0, 5)}[/tex]
Intersectiile cu axele sunt punctele A(5/2, 0) si B(0, 5).
