If you are trying to find what \(\displaystyle n\) is equal to in \(\displaystyle n\,=\,29.26\,-\,2k\)

When \(\displaystyle k\,=\,8.44\), then you substitute \(\displaystyle k\) in your equation:

\(\displaystyle \L \;n\,=\,29.26\,-\,2(8.44)\)

Then follow the Order of Operations, first multiplication: \(\displaystyle \L \;n\,=\,29.26\,-\,16.88\)

Finally subtraction: \(\displaystyle \L \;n\,=\,12.38\)