Question 489785
I need help in finding the coordinates of the vertex for the parabola defined by the given quadratic function f(x) = -x^2 -4x + 8
**
Given function is a parabola of the standard form: -A(x-h)^2+k, with (h,k) being the (x,y) coordinates of the vertex. A is a multiplier which affects the steepness or slope of the parabola. The minus sign of the lead coefficient means that the parabola opens downwards, that is, it has a maximum.
..
Finding the coordinates of the vertex:
f(x) = -x^2 -4x + 8
completing the square
y=-(x^2+4x+4)+8+4
y=-(x+2)^2+12
Ans:
Coordinates of the vertex: (-2,12)
See graph below as a visual check on the answer:
..
{{{ graph( 300, 300, -10, 10, -20, 20, -x^2 -4x + 8) }}}