Can someone show me how can be factorise or rearrange into
thanks
If you examine with numbers first, then it will be clearer with "k" introduced.
If we divide any value by 4 and then multiply by 4, that will bring us back to the original value.
Hence
In terms of the example you have
is a common factor,
and to make a common factor also, we write as
Hence we get as a common factor