Question

Graph the parabola Y=x^ +2x -1Plot five points on the parabola the vertex the two points to the left of the vertex the two points to the right of the vertex then click on the graph a function button

Answer 1

Given the equation of the parabola

`y=x^2+2x-1`

which can be written as

`\begin{gathered} y=x^2+2x+1-1-1 \\ =(x+1)^2-2 \end{gathered}`

Comparing with

`y=a(x-h)^2+k`

gives a = 1, h = -1 and k = -2.

The vertex is (h, k) = (-1, -2).