SOLUTION: Hi, I'm having trouble figuring out a parabola's equation. The Y intercept is (0,6), the vertex is (2,8). These are the only points given. Can you please explain to me how to work
Algebra.Com
Question 752747: Hi, I'm having trouble figuring out a parabola's equation. The Y intercept is (0,6), the vertex is (2,8). These are the only points given. Can you please explain to me how to work out the equation/what it is?
Thanks a lot,
Nathan
Found 2 solutions by rothauserc, josmiceli:
Answer by rothauserc(4718) (Show Source): You can put this solution on YOUR website!
Find the equation of the parabola with Y intercept (0,6) and the vertex is (2,8). These are the only points given.
The vertex form of a quadratic function is
y=a(x−h)^2 + k
where (h,k) is the vertex. Use your given vertex, and solve for a using the fact that you know the y-intercept.
Note that the vertex and any other point on the curve would be sufficient.
y = a(x-2)^2 + 8
6 = a(0-2)^2 + 8
6 = 4a + 8
4a = -2
a = -1/2
y = (-1/2)(x-2)^2 + 8
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
The general form is
where is the y-intercept,
(0,6),so now you have
The x-coordinate of the vertex,
(2,8), is , so
So far, you have:
Now plug in the point ( 2,8 )
and
------------
answer
--------------------------
Is the vertex at (2,8) ?
and
OK
Here's a plot of the equation:
RELATED QUESTIONS
I am having trouble figuring out what the slop intercept is for y=1/4x-2 (8 -1) (answered by Alan3354)
Hi, I have a few questions I'm having an extremely hard time figuring this out.
1.... (answered by Fombitz)
A parabola has vertex (3,-1) and an x intercept at (5,0).
a). What is the other x... (answered by stanbon)
I am having a lot of trouble figuring this question out: F(x)= -2(x-3)^2+8 , what is the... (answered by josgarithmetic)
Hi I am having trouble finding the vertex or vertex form of this parabola
y=2x^2-x+2
(answered by lynnlo)
Hi, I am having trouble figuring out this problem. Would someone please help me figure... (answered by mathsteacher)
The vertex of a parabola is (-1.5, -12.5), and its y-intercept is (0,... (answered by josgarithmetic)
Hello, I am having a hard time with the following two problems. Could someone please help (answered by Alan3354)
I am just having trouble figuring out exactly where to start I have gotten a little ways... (answered by mananth)