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

solution:

→c= a b , that is product of a and b is possible only when when a is m × n matrix and b is n × p matrix.

that is, number of columns of a= number of rows of b.

so, size of matrix , c= a b is , if a = (m × n)matrix

b= (n × p)matrix

then a b = [ (m × n)matrix] ×[   (n × p)matrix ]

→→c= a b= [m × p ] matrix

→→size of product a b will be equal to = number of rows of a × number of columns of b

answer: i think it is (1,-2)