Let n = 5. what is the value of the expression 9n2−2−n ?

Hey Chrasedaouuovw!

This question is pretty simple in the sense that all you have to do it plug in 5 instead of n!
You start off with plugging it in: 9(5x5)-2-5
Then you do your parenthesis first, 5x5=25, so you now have 9(25)-2-5
You can combine like terms: 9(25)-7
Now you can multiply 9 by 25 which equals 225!
So you're left with 225-7, which equals 218!

Hope I was able to help! If you have any further questions, please let me know!