How do I write the formula 1/(square root(x + 5))

You go to Insert > Equation
Then you choose Equation Tools>Design>Fraction and pick a style from the top row
Then you click on the top box which has been added to the page. Type 1
Then you click on the lower box and select Equation Tools>Design>Radical
Then you click on that box and type 'x+5'

If you can't follow these instructions, go to youtube and do a search for 'Word Equation Editor' and watch a few videos.

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Andrew Lockton
Chrysalis Design, Melbourne Australia

Your instructions don't seem to apply.

Under Equation there is no Tools

I am not using Word 2010 anymore so I'm not sure what the ribbon tab is called back there. In Word 2013 and 2016 the first step opens a context sensitive ribbon tab called "Equation Tools>Design". If that doesn't happen on Word 2010 then is there a context sensitive ribbon there with a different name?

Try the last instruction and look at youtube for Word 2010 specific videos. What you are asking is relatively straightforward and you should be able to find plenty of videos that teach you the basic concepts.

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Andrew Lockton
Chrysalis Design, Melbourne Australia