# How do you write a variable expression for the word phrase "a number decreased by 8"?

Jan 20, 2016

#### Answer:

$y = x - 8$

#### Explanation:

When you say a number decreased by eight, then it means that there are 2 defined numbers, and the difference between the 2 numbers is eight.
So there's some defined $y$ and a defined $x$ such that $y - x = 8$ so that means $y = x - 8$