Question 28694: For the function y=x^2-6x+8, perform the following tasks:
Put the function in the form y=a(x-h)^2+k
What is the line of symmetry? Found 2 solutions by venugopalramana, josmiceli:Answer by venugopalramana(3286) (Show Source):
You can put this solution on YOUR website! For the function y=x^2-6x+8,
={X^2-2(X)(3)+3^2}-3^2+8
=(X-3)^2-1
perform the following tasks:
Put the function in the form y=a(x-h)^2+k
Y=1(X-3)^2-1
What is the line of symmetry?....X-3=0....OR....X=3 IS THE LINE OF SYMMETRY.
You can put this solution on YOUR website! [1]
[2]
expand this
Since the coefficient of x^2 is 1, make a = 1
group the constant terms together
Set the coefficients on the left equal to those on the right
-2h = -6
h = 3
h^2 + k = 8
9 + k = 8
k = -1
going back to [2]
expand this to check
OK
What is the axis of symmetry?
x = +3
check
does x + a give me the same y as x - a for any value of a?
plug in some values for x
y(3 + 1) = 0
y(3 - 1) = 0
y(3 + 2) = 3
y(3 - 2) = 3
a far out one
y(3 + 12) = 143
y(3 - 12) = 143
OK
