Posted by HELP on Thursday, September 5, 2013 at 5:11pm.
I have a graph with a parabola on it and asked to write the function for f(x) in standard form.
I know that standard is y=ax^2+bx+c obviously, since the points are on the graph we know x and y so a,b and c need to be found. The vertex is on (4,-4) the points on the left side of the parabola from the vertex up are (3,-3) (2,0) and (1,5). On the right side upwards from the vertex is (5,3) (6,0) and (7,5) I started at the origin to find all the points so if u plot them all and draw te curved lines u will have what I have. Now what do I do???
- Algebra 1 parabola's - Reiny, Thursday, September 5, 2013 at 6:03pm
from the vertex (4,-4)
we can say that parabola must be
y = a(x-4)^2 -4
to find the value of a, let's use one of the other points
5 = a(-3)^2 - 4
9 = 9a
a = 1
so the parabola is
y = (x-4)^2 -4 or
y = x^2 - 8x + 12
I will leave it up to you to make sure all those other points we did not use are also on this curve by subbing them into our equation.
They should all satisfy the equation,
e.g. I will use (7,5)
LS = 5
RS = 49 - 56 + 12 = 5 = LS
so far so good!
- Algebra 1 parabola's - Taylor, Thursday, September 5, 2013 at 6:11pm
Thanks so much!!!
Answer this Question
- Algebra - I have a graph here. The vertex is (4,-4), then the points (3,-3) and...
- Alg II/Trig - A parabola has a vertex at (0,0); a horizontal axis; and the point...
- algebra II - Can you please help me with the these problems. 8.Write an equation...
- Algebra: Parabolas - I have a math problem that requires me to find the focal ...
- math - the points (-9,0) and (19,0) lie on parabola. a.) determine an equation ...
- Algebra - I am given a graph of a parabola and I have to write a function in at ...
- algebra - 1)What is the distance between the museum and sailing club.I cant post...
- Algebra - what is the equation, in standard form, of a parabola that contains ...
- algebra - what is the equation in standard form of a parabola that contain the ...
- Math - write an equation in standard form of the parabola that has the same ...