# How do you find an equation of a parabola given endpoints of latus rectum are (-2,-7) and (4,-7)?

##### 1 Answer

Aug 3, 2017

The vertex form of a parabola of this type is:

where

The x coordinate of the vertex, h, is the midpoint between the x coordinates of the two points:

We know that

We are not told whether the parabola opens up or down and you have only asked for one of the two possible equations, therefore, I shall choose the positive value:

We can find the value of k substituting in one of the points: