Can someone help with getting the equation?

y = -2x² + 8x + 10

Step-by-step explanation:

let's adjust the coordinates of vertex to a whole number: (2 , 17.75) to (2 , 18)

Quadratic equation: y = ax² + bx  c    or    y = a(x-h)² + K  (h,k) is the vertex

y = a (x-2)² + 18

a = (y-18) / (x-2)² = (16-18) / (1-2)² = -2    : calculate use point (1 , 16)

y = -2 (x-2)² + 18

y = -2x² +8x + 10

i found two solutions,   n = 2 • ± √3 = ± 3.4641

step-by-step explanation: