Sketch a graph the parabola: 𝑦 = 𝑥 2 − 6𝑥 + 8. Identify the x-intercept(s), y- intercept, and vertex.

Answer 1

y=x^2-6x+8

complete the square

y=x^2-6x +8

y=x^2-6x+9-9+8

y=(x-3)^2-1

vertex=(3,-1)

set y=0 to find the x-intercepts

0=x^2-6x+8

factor

(x-4)(x-2)=0

x-4=0

x=4 is one x-intercept

x-2=0

x=2 is the other x-intercept

set x=0 to find the y-intercept

y=0^2-6*0+8

y=8 is the y-intercept