The set of real numbers which satisfies the equation x²=4 ​

Based on what i know about mean, this doesn't add up.

Abag has more green balls than blue balls, and there is at least one blue ball. let bb represent the number of blue balls and let gg represent the number of green balls. let's compare the expressions 2b2b and b + gb+g. which statement is correct? choose 1

Graph y ≥ -x^2 - 1. click on the graph until the correct graph appears.