# Check my precalc?

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#1: f(x) = x^2-4x
find vrtex, axis ofsym, y-int, x-int if any, domain, range, where increasing and decreasing.

I got.... vertex: 2,4
axis of sym: x=2
D= (-infinity, infnity)
range= [4,infinity)

im stuck of the intercepts because when i plug i 0 for x i get yint of 0 but the graph doesnt show that.

Am i doing the completingthe square wrong
I got (x^2-2)^2 + 4

#2 Same requirements as the first question
f(x)= x^2 + 6x +9
I got... vertex: (-3,18)
axis of sym: x=-3
Domain= (-infinity, infinity)
Range= [18, infinity)

y-int (0,9)
x-int idk???

After completing the square I got:
(x+3)^2 + 18
Also a question, how do you know if there is an x or y int without drawing the graph because my graph des not show a xint but the equation does?

Thanks!

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