SOLUTION: 20. I need help graphing the following and listing the directions,vertex,axis of symmetry,table with 5 points and the graph for this equation f(x)=x^2-2x-5

Question 1157013: 20.
I need help graphing the following and listing the directions,vertex,axis of symmetry,table with 5 points and the graph for this equation
f(x)=x^2-2x-5
Found 2 solutions by josgarithmetic, Boreal:
Answer by josgarithmetic(39617) (Show Source): You can put this solution on YOUR website!

You already see f contains a point (0,-5).

Try completing the square.

Vertex is (1,-6).

Directrix:
, the lead coefficient
, distance of vertex from either focus or directrix
-
----------the Directrix

Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
the vertex x point is at -b/2a and b is -2 and a is the coefficient of x or 1
so the vertex x point is +1
f(1)=1-2-5=-6
so the vertex is at (1, -6)
The axis of symmetry is the x-value or x=1
for 5 points,
first pick x=0, and f(0)=-5. that is easy
the vertex is a point, so you have that.
Try -1 and you get 1+2-5=-2
try 2 and you get -5
because -1 is two units away from 1, and +3 is two units away from 1, and the function is symmetrical, the y-values are the same. So f(-1)=f(3)=-2
if you look at f(-2) three units from the axis, f(4) is also 3 units away, and they have the same y-value.

RELATED QUESTIONS
17. I need help graphing the following and listing the directions,vertex,axis of... (answered by josgarithmetic)
19. I need help graphing the following and listing the directions,vertex,axis of... (answered by Boreal)
15. f(x)=-(x+4)^2 I need help graphing the following and listing the... (answered by josgarithmetic,MathTherapy)
14. I need help graphing the following and listing the directions, vertex, axis of... (answered by Alan3354)
16. I need help graphing the following and listing the directions, vertex, axis of... (answered by MathLover1)
18. I need help graphing the following and listing the directions,vertex,axis of... (answered by MathLover1)
Please help me list the directions,vertex, axis of symmetry, table of 5 points, graph... (answered by MathLover1)
Identify the axis of symmetry, create a suitable table of values, and sketch the graph... (answered by Earlsdon,scott8148)
I need the vertex, Axis of Symmetry, (answered by ewatrrr,richwmiller)