Given equation of the parabola y= -5x^2 -10x -13.
We need to apply formla for x-coordinate of the vertex.
x=-b/2a.
For the given equation we have a=-5 and b=-10.
Plugging values of a and b in formula of x-coordinate of the vertex.
x= -(-10)/2(-5)
x= 10/(-10) = -1.
So, we got x-coordinate of the vertex = -1.
Now, we need to plug x=-1 in given equation to find the y-coordinate of the vertex.
Plugging x=-1 in y= -5x^2 -10x -13, equation we get
y=-5(-1)^2-10(-1)-13.
y= -5(1) +10 -13.
y=-5 +10-13.
y=-18+10.
y=-8.
So, we got y-coordinate of the vertex -8.
Therefore, vertex of the parabola is (-1,-8).
