Evaluate lim(x,y)(0,0)8xyx2+y2\displaystyle \lim_{{{\left({x},{y}\right)}\to{\left({0},{0}\right)}}}{\frac{{-{8}{x}{y}}}{{{x}^{{2}}+{y}^{{2}}}}} = .

Use DNE for does not exist, oo for infinity or -oo for negative infinity.