# Write an algebraic expression for the quantity. Let x represent the unknown value. Seven times a...

## Question:

Write an algebraic expression for the quantity. Let {eq}x {/eq} represent the unknown value.

Seven times a quantity decreased by thirteen

## Algebraic Expressions:

Algebraic expressions are translations from English to Mathematics. When writing a sentence as a mathematical expression, it is helpful to break the sentence down into the pieces that describe the operations. In most cases when writing an algebraic expression, the sentence is worked from right to left.

## Answer and Explanation:

As given in the problem, let {eq}x {/eq} represent the unknown value. Then break each part of the sentence down and write as a mathematical expression. Typically you work the sentence from right to left.

"a quantity decreased by thirteen" {eq}\implies ~ x - 13 {/eq}

"seven times a quantity decreased by thirteen" {eq}\implies ~ 7(x - 13) {/eq}