Question

Determine the vertex of
f(x) = x^2 + 8x - 5

Answer 1

The vertex forgiven equation is (-4,-21).

Explanation:

We have given a quadratic equation.

f(x) = x²+8x-5

We have to find the vertex of the given equation.

Let (h,k) be the vertex for the quadratic equation.

h = -b/2a

From given equation, we have

a = 1 , b = 8 and c = -5

then , h = -8 / 2(1)

h = -8/2

h = -4

Putting the x-coordinate of vertex in given equation, we get the y-coordinate of vertex.

f(x) = (-4)²+8(-4)-5

f(x) = 16-32-5

f(x) = -21

Hence, the vertex for given equation is (-4,-21).

Answer 2

Answer: (-4,-21)

Explanation:

Apply the formula for calculate the x-coordinate of the vertex of the parabola:

`x=(-b)/(2a)`

Where:

a=1 and b=8

Then, this is:

`x=(-8)/(2*1)=-4`

Now you must substitute x=-4 into the function to obtain the y-coordinate of the vertex.

Then, this is:

`f(x)=y=(-4)^(2)+8(-4)-5=-21`

Therefore the vertex is:

(-4,-21)