Question 64703
f(x)=x^2-6x
{{{ graph( 300, 200, -10, 10, -10, 10, x^2-6x )}}} (graph 300x200 pixels, x from -10 to 10, y from -10 to 10, of function x^2-6x) 
x^2-6x=0
x(x-6)=0
x=0 intercept
x-6=0
x=6 intercept
x=(0+6)/2
x=6/2
x=3
y=3^2-6*3
y=9-18
y=-9 vertex is (3,-9)