equations and interval notation

[haliebre]

A few more questions. I need to solve x2 -4<= 0 Write the solutino in interval notation.

I also need help in solving this using the elimination method.

5x-27=6
y=5/2x-4

 

[pka]

\(\displaystyle x^2 - 4 \le 0\quad \Rightarrow \quad (x + 2)(x - 2) \le 0\quad \Rightarrow \quad - 2 \le x \le 2\quad \Rightarrow \quad x \in [ - 2,2].\)

 

[haliebre]

thanks. It has been ten years since I took algebra so I am still trying to relearn a lot of information.