Question

How do you write a variable expression for the word phrase “$3$ less than $5$ times a number” ?

Answer 1

Hint: In the given question, we are required to write an algebraic expression based on the information given to us. First, break down the information given to us to try and identify what algebraic expressions must look like. You should always know what you are dealing with. A sum means that you are adding something, so you are going to use the $ + $ sign.

Complete step by step answer:
The word phrase “$3$ less than $5$ times a number” means we will first assume the number to be any variable and then form an algebraic expression with the same variable as assumed. Now, according to the word statement, we multiply the number assumed with five and then subtract three from the resultant expression.So, let us assume the number to be $x$. Then, we have five times the number as $5x$. Then, we subtract $3$ from the resultant expression. So, subtracting three from the expression, we get,
$5x - 3$

Therefore, the algebraic expression for the above statement is $\left( {5x - 3} \right)$.

Additional Information: When we combine numbers and variables in a valid way, using operations such as addition, subtraction, multiplication, division, exponentiation, and other operations and functions as yet unlearned, the resulting combinations of a mathematical symbols is called a mathematical expression.

Note: An expression is a sentence with a minimum of two numbers and at least one math operation. This math operation can be addition, subtraction, multiplication, and division. A math expression is different from a math equation. An equation will always use an equivalent $\left( = \right)$ operator between the two terms. It is not a surprise that variables act like pronouns, because math is basically its own language, defined by numeric and logical rules.