Question

How do you write the variable expression for "number b is decreased by the number a"?

Answer 1

`b- a`

Explanation:

"decreased by" means made less by.

`10 " decreased by 4 means " 10-4 = 6`

a and b also just represent numbers.

We do exactly the same..

`b -a`

However, as these are variables and unlike terms, this is all we can do until we know actual numbers to use.