SOLUTION: Can someone please help me with this problem? I can't get it. Given f(x) = x^2 – 8x - 20 equation (parabola), find the following: 21. The vertex 22. The y-intercept(s) Th

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Question 64803: Can someone please help me with this problem? I can't get it.
Given f(x) = x^2 – 8x - 20 equation (parabola), find the following:
21. The vertex
22. The y-intercept(s)
Thanks a lot

Found 2 solutions by Earlsdon, venugopalramana:
Answer by Earlsdon(6294)   (Show Source): You can put this solution on YOUR website!
Find the vertex and y-intercept of:
Rewrite as:

The x-coordinate of the vertex is given by:
(See the general form:
In your equation, a = 1 and b = -8

Substitute this into the original equation and solve for y.



The vertex is at: (4, -36)
The y-intercept is found by substituting x = 0 and solving for y.


The y-intercept is at: (0, -20)

Answer by venugopalramana(3286)   (Show Source): You can put this solution on YOUR website!
Can someone please help me with this problem? I can't get it.
Given f(x) = x^2 – 8x - 20
y = [x^2-2x*4+4^2]-4^2-20
y = (x-4)^2-36
hence x=4 and y =-36 is the vertex.....(4,-36)
hence y intercept is -36.
when y=0,we get
(x-4)^2=36
x-4 = 6 or -6
x=6+4=10.............or...........-6+4=-2
10 and 2 are the x intercepts.
equation (parabola), find the following:
21. The vertex
22. The y-intercept(s)

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