# Algebra

posted by .

I have a parabola that I have to write as an equation I found the vertex as (-3,-2) and the following points (-4,-1)(-2,-1),(-5,2),(-1,2).

I can't seem to come up with the correct equation. I'm using the formula y=a(h-k)^2+k but I'm not doing something right. Can anyone help me?

• Algebra -

the formula is wrong. it should be
y = a(x-h)^2 + k
where (h,k) is the center
then to solve for a, you choose one of the points to substitute for the value of x and y. for instance you choose (-4,-1):
y = a(x-h)^2 + k
-1 = a(-4+3)^2 - 2
then solve for a.

if you want to make sure that you got the correct points on the parabola, if they are substituted in the equation, they should give the same value of a.

hope this helps~ :)

## Similar Questions

1. ### math help,algebra

Okay this is what i have to do but i think i am doing something wrong. directions are: Identify the axis of symmetry, create a suitable table of values, and sketch the graph (including the axis of symmetry). The problem is: y = -x^2+6x-2 …
2. ### math

write an equation for the parabola with focus (1,3) and vetex (0,3) See the paragraph Analytic Geometry Equations. You will have a choice of equations, you did not state whether the axis of symettry was parallel to x or y axis. http://en.wikipedia.org/wiki/Parabola …
3. ### algebra

1)What is the distance between the museum and sailing club.I cant post the graph or anything but I have my numbers right its 53 but I used the distance formula so its either 53 units or the square root of 53 units. 2)Write the equation …
4. ### algebra

1)Write an equation for the parabola with focus (1,3)and vertex(0,3) answer= x= 1/4(y-3)^2 2)Write an equation for a circle if the endpoints of a diameter are at (1,1)and(1,-9) answer= (x-1)^2+(y+4)^2=25 3)Which is the equation of …
5. ### algebra problem

I need to find the equation of a parabola. I am not sure if this is the correct way or if I have the correct answer. Vertex at origin, focus is at (0,3) Equation of parabola vertex (0,0) focus (0,3) focus (h,k+p) (0,0+3) y=0-3 directrix …
6. ### Algebra

Can someone tell me if I am right? I need to find the equation of a parabola. I am not sure if this is the correct way or if I have the correct answer. Vertex at origin, focus is at (0,3) Equation of parabola vertex (0,0) focus (0,3)
7. ### Maths

Hi, need a bit of help on this one. A straight line passes through the points (4,3) and (10,0), I need to write down the equation of the line in the form y=mx+c, I have tried but I cant seem to get the second coordinates to satisfy …
8. ### pre cal

What is the center of the conic whose equation is x^2 + 2y^2 - 6x + 8y = 0 2.Which one of the following equations represents a hyperbola?
9. ### Algebra 1 parabola's

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 …
10. ### algebra 2

A quadratic equation can be written in vertex form or in standard form. Sometimes one form is more beneficial than the other. Identify which form would be more helpful if you needed to do each task listed below and explain why a. factor …

More Similar Questions