Question 1082845

Write an equation of a quadratic function given the vertex and another point on the graph.

Vertex: (–5, –10)

Point: (0, 15)
<pre>Vertex form of a quadratic equation: {{{y = a(x - h)^2 + k}}}
{{{15 = a(0 - - 5)^2 - 10}}} ------ Substituting (0, 15) for (x, y), and (- 5, - 10) for (h, k)
15 = 25a - 10
15 + 10 = 25a
{{{matrix(1,5, 25/25, "=", a, "=", 1)}}}
{{{highlight_green(matrix(1,3, y, "=", (x + 5)^2 - 10))}}} ------ Substituting 1 for a, and (- 5, - 10) for (h, k)