Answer:
180 meters
Step-by-step explanation:
The function you have here is negative function meaning the function has a concave down parabola (if you graph it on desmos or a graphing calculator you'll see what I'm talking about).
So they gave it to you in factored form and asked you to find the max. The max of this function is at the vertex of the parabola. In order to find the vertex you have distribute or multiply to get the original polynomial.
-5(x-8)(x+4)
-5(x^2+4x-8x-32)
-5(x^2-4x-32)
-5x^2-20x-160
Vertex formula is: -b/2a
b = 20
a = -5
[tex]\frac{-20}{2(-5)}[/tex]
= 2
The x-coordinate of the vertex is 2.
Plug 2 into the equation
-5(2)^2+20(2)+160
= 180 meters
