How do you write a variable expression for the word phrase "the sum of 9 and a number"?

1 Answer
Jan 5, 2016

In math, any number you don't know - and/or want to find can be named after whatever you want, but there are some conventions.

Explanation:

The most common letter used is #x#, but you won't find it strange when the variable comes as #y#, #a#, #b#, #t#... And it makes no difference!

If #x+1=2# and #y+1=2#, what's the difference? None!

In this case, you can rename it as #9+x#, using the most commonly used letter in the alphabet!