[tex]=x^{2} -6x+5[/tex]

a) y-intercept = 5
b) [tex](x-1)(x-5)[/tex]
step 1: find factors of 1st and last terms
step 2: multiply the factors "rainbow" style (like in the picture) and add the products to make sure they equal the middle term
[tex]x^{2} -6x+5\\1,1[/tex][tex]-1,-5[/tex]
[tex](-1)+(-5)=-6\\=(x-1)(x-5)[/tex]
c) [tex]x=1,5[/tex]
[tex](x-1)(x-5)\\x-1=0[/tex][tex]x-5=0[/tex]
[tex]x=1[/tex] [tex]x=5[/tex]
d) AoS= [tex]x=3[/tex]
e) [tex]vertex=(3,-4)[/tex]
[tex](h,k)\\h=-\frac{b}{2a} \\h=-\frac{(-6)}{2(1)} \\h=-(-3)\\h=3\\k=f(3)=(3)^2-6(3)+5\\k=9-18+5\\k=-4[/tex]