Determine if the function is an even function, an odd function or neither. y=-5x^(2)-2x+6

By definition we have:
 A function is even if, for each x in the domain of f, f (- x) = f (x). The even functions have reflective symmetry through the y-axis.
 A function is odd if, for each x in the domain of f, f (- x) = - f (x). The odd functions have rotational symmetry of 180º with respect to the origin.
 For y = -5x ^ (2) -2x + 6 we have:
 f (-x) = - 5 (-x) ^ (2) -2 (-x) +6
 f (-x) = - 5x ^ (2) + 2x + 6
 
 the function is neither