The quadratic function is given by the formula y = -x ^ 2 + 4x- 9. Find the coordinates of the vertex of the parabola.

We are given a quadratic function, the graph of which is a parabola with branches down.

Let’s write down the coefficients: a = – 1, b = 4, c = – 9.

(m; n) – the coordinates of the vertex of the parabola are found by the formulas m = – b / 2a and n = y (m).

m = – 4 / (- 2) = 2.

n = y (2) = – 4 + 8 – 9 = – 13 + 8 = – 5.

Answer: (2; – 5) the vertex of this parabola.