Answer
a)yes
b)no
c)yes
d)no
Work Step by Step
We can check whether they solve the inequality by plugging in the different values and seeing if they satisfy the inequality:
a) $(-2)^2-2(-2)-8=4+4-8=0\geq0$, thus yes
b) $(0)^2-2(0)-8=0+0-8=-8\lt0$, thus no
c) $(-4)^2-2(-4)-8=16+6-8=16\geq0$, thus yes
d) $(1)^2-2(1)-8=1-2-8=-9\lt0$, thus no
