The answers to the question are are the equations
y = 0.08x²-1.6x+13
y = 0.08(x-10)²+5
David starts at (20, 13) and skates along a path that can be modeled by a quadratic function with a vertex at (10, 5).
Vertex form of quadratic function is
y = [tex]a(x-h)^2+k[/tex]
13 = a(x-10)²+5
let x = 20
a(20-10)²+5
13 = 100a + 5
take like terms
13 - 5 = 100a
8 = 100a
divide through by 100
a = 0.08
hence the equation would be
y = 0.08(x-10)²+5
Read more on equations here:
https://brainly.com/question/9621134
#SPJ1