Question

What is the vertex of `y= x^2+4x-1`?

Answer 1

The vertex is graph{x^2 + 4x -1 [-10, 10, -5, 5]} `v(-2, -1)`

Explanation:

Given `f(x) = y = ax^2 + bx + c " "` form of the equation
The vertex, `v(h, k)`
`h = -b/(2a); and k = f(h)`
Now `f(x) = x^2 + 4x - 1`
`h = - 4/2 = -2; f(-2) = -1`
Thus `v(-2, -1)`