Question

How do you write the equation of the parabola in vertex form given the vertex (-2, -8) and passes through the point (7, -494)?

Answer 1

`y =- 6(x+2)^2 - 8`

Explanation:

The equation of a parabola in vertex form is

`y = a(x - h)^2 + k`
where (h , k ) are the coords of the vertex.

here the coords of the vertex are given and so

`y = a(x + 2 )^2 - 8`

now also given a point (7 , -494) that the parabola passes thro'.
substitute x = 7 and y = -494 into the equation and solve for a.

hence `-494 = 81a - 8 → a = -6`