[tex]x^2-6x+8=0\\\Delta=36-4.1.8\\\Delta=4[/tex]
[tex]X_v=- \frac{-6}{2} ~~~X_v=3[/tex]
[tex]Y_v= -\frac{4}{4} ~~~Y_v=-1[/tex]
(3,-1)
2°
[tex]x^2-10x+25=0\\\Delta=100-4.1.25\\\Delta=0[/tex]
[tex]X_v=- \frac{-10}{2} ~~X_v=5[/tex]
[tex]Y_v= \frac{0}{4} ~~~Y_v=0[/tex]
(5,0)
3°
[tex]3^x=27\\3^x=3^3[/tex]
[tex]x=3[/tex]
