Question

Find the vertex and axis of the symmetry of the graph of the function.
f(x) =x^2-8x

Answer 1

Graph the equation, the turning point of the graph is the vertex, the x coordinate of the vertex is the axis of symmetry.

Answer 2

How do I find the vertex and x coordinate?

Answer 3

You graph the equation

Answer 4

No, there is more to that. It's a question on my homework and there isn't a graph

Answer 5

This is what the graph is.

Answer 6

The axis of symmetry is x = 4 , and the vertex is (4,-16)

Answer 7

how did you find that?

Answer 8

I graphed the equation, f(x) = x^2 -8x just means y = x^2 - 8x

Answer 9

You could also put it into the completed square form and it will give you the axis of symmetry which you can use to find the vertex

Answer 10

hmmm I still not sure how to do that. This qustion on my homework doesn't have a graph. How do you do it without a graph?

Answer 11

If your assignment asks you to find the vertex and axis of symmetry without a graph of it, i assume your class has taught you how to graph functions?

Answer 12

yes

Answer 13

writing the equation in y = a(x – h)2 + k
gives the vertex, (h,k) are the coordinates to the vertex.

Answer 14

the standard equation of a parabola is y = ax2 + bx + c.

Answer 15

Can you please show me the steps on how you came up with the answer without the graph please?

Answer 16

Okay.

Answer 17

y = x^2 -8x
To find the x coordinate of the vertex ( the axis of symmetry )we use the equation
-b/2a.
so -(-8)/2(1)
8/2
= 4

Answer 18

x = 4.

Answer 19

then substitute that value into y = x^2 - 8x
to get the y-coordinate of the vertex
y = (4)^2 - 8(4)
y = 16 - 32
y= -16

Answer 20

does this make sense?

Answer 21

Thank you so much. It's easier for me to understand when I see it.