h(-3)=-2x^2+3x-1

Presumably h(x) = -2x² + 3x -1 and you want to evaluate h(-3).  If so then replace the x's by -3:

h(-3) = -2*(-3)² + 3*(-3) -1

        = -2*9 -9 -1

        = -18 -9 -1

        = -28