Problem with a simple exercise
So I have to solve the equation $$y^2=4\tag{1.9.88 unit 3*}$$
I did this: $$y^2=4 \text{ means } \sqrt{y^2}=\sqrt{4}=>y=2$$
But I have a problem, $y$ can be either negative or positive so I need to do: $$\sqrt{y^2}=|y|=2=>y=2- or- y=-2$$
Is it right?
Yes, it is right. I'll recommend a better way to approach this. Just factorize it.