Answer:
[tex]x=\{-\frac{1}{2} ,\:0\}[/tex]
Step-by-step explanation:
[tex]f(x) =-2x^2 -x\\plug \: f(x) =0\\0= -2x^2 -x\\2x^2 + x = 0\\x(2x+1) = 0\\\therefore x =0 \: or \: 2x+1 = 0\\\therefore x =0 \: or \: 2x = -1\\\\\therefore x =0 \: or \: x = -\frac{1}{2} \\\\x=\{-\frac{1}{2} ,\:0\}[/tex]
