Answer:
D (The last choice)
Step-by-step explanation:
We know that rays are lines with a dot on one side and an arrow on the other. WE also know that lines have two arrows on each end. Keeping this in mind, we can identify which line segments and rays and lines.
x ∉ R
x² = - 21
if x² < 0 => x ∉ R
a = 0,-7
a^2 + 7a=0
Factor out an a
a(a+7) =0
Using the zero product property
a=0 a+7 =0
a =0 a= -7
