X^2-16=0 solve for all real values of x

Hi there! Use the difference of two squares formula below:

You need to know that what number times itself and get 16. 16 comes from 4×4 or 4².

Then,

Solve the equation for all real values of x.

If you don't like using a formula. You can do this:

If you remember the square root well, the square root of 16 is 4×4. Pull out the two 4's and thus the square root of 16 is 4.

For the square both sides method above (second method), we can define that:

Answer

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.