# Math Help - parabola problem

1. ## parabola problem

hi all I have a question, and after a few hours of looking in my books I cant find the answer.

I have the poin (-4,56) and I am asked to show if it is on the parabola, but I just cant remeber or find the solution?

sorry to be a pain

Dave

2. ## Re: parabola problem

Originally Posted by davellew69
hi all I have a question, and after a few hours of looking in my books I cant find the answer.

I have the poin (-4,56) and I am asked to show if it is on the parabola, but I just cant remeber or find the solution?

sorry to be a pain

Dave
Hi davellew69,

Do you have the equation of the parabola? If so, substitute the coordinates you have into the equation and see if it makes it true. You really haven't given much detail to work with.

3. ## Re: parabola problem

the equation is y+2x^2-7x-4 but I`m not sure what you mean by substuting

4. ## Re: parabola problem

Originally Posted by davellew69
the equation is y+2x^2-7x-4
Sorry, that's not an equation. Is it $y=2x^2-7x-4$? I think it is. Now, substitute your coordinates in for x and y and see if it is true.

$(-4, 56) \Longrightarrow 56 = 2(-4)^2 - 7(-4)-4$

Is that true? If it is, then the point (-4, 56) lies on the parabola.

5. ## Re: parabola problem

lol got it, thanks, I must seem a right plonker

6. ## Re: parabola problem

Originally Posted by davellew69
lol got it, thanks, I must seem a right plonker
No worries, mate.