Answer:
Option D
Step-by-step explanation:
Whenever we take a square root of a number the ± sign is with it like here in the question
[tex]x^2=20\\\\Apply\ square\ root\ on\ both\ sides\\sqrt{x^2}=\sqrt{20} \\\\The\ square\ cancels\ out\ with\ the\ root\x=\sqrt{20}[/tex]
And then x = ±4.47 which means x has two values one is +4.47 and the other is -4.47 so Option D is our answer.
