Question

Solve Y=-0.02x^2+1.3x+8

Answer 1

Assuming the question requires the zeroes of Y(x).

Multiply by 50 (to get integer coefficients)
50*y(x)=-x²+65x+400=0
Solve by quadratic formula:
x=(-65±√(65²+1600))/-2
=5.66 or 70.66 approximately