## Babynini one year ago Parabolas and equations

1. Babynini

2. Babynini

@rvc

3. Babynini

@ganeshie8

4. ganeshie8

First of all notice that the parabola with a directrix equation x = -1/3 opens to the right : |dw:1433218519063:dw|

5. Babynini

It's not the x line that is moving up and down, but rather y moving?

6. ganeshie8

the general form of equation of parabola that opens to right is $\large x = \frac{1}{4c}y^2$ where $$c =$$ distance between directrix and vertex

7. ganeshie8

|dw:1433218643337:dw|

8. ganeshie8

so the equation would be $\large x = \frac{1}{4*\frac{1}{3}}y^2$ simplify

9. Babynini

0.75y^2

10. Babynini

or 3/4y^2

11. ganeshie8

x = 3/4 y^2

12. ganeshie8

it is an equation, so you need to write the left hand side also ok

13. ganeshie8

the equation of parabola in question is $x = \frac{3}{4}y^2$

14. Babynini

Yep :) thank you so much!! I had been accidentally writing it like |dw:1433218892849:dw| so that's why it was all wack

15. ganeshie8

i see.. remember x = k is a "vertical line"

16. Babynini

I shall from now on ^-^ hah