## Algebraic Expressions With Example Problems and Interactive Exercises

Use the complying with examples and also interenergetic exercises to learn about Writing Algebraic Expressions.

You are watching: Seven less than twice a number equals 19  Problem: Ms. Jensen likes to divide her class into teams of 2. Use mathematical signs to recurrent all the students in her course.

Solution: Let g represent the number of groups in Ms. Jensen"s course.

Then 2 · g, or 2g have the right to represent "g teams of 2 students".

In the difficulty above, the variable g represents the number of groups in Ms. Jensen"s course. A variable is a symbol supplied to represent a number in an expression or an equation. The worth of this number have the right to differ (change). Let"s look at an example in which we usage a variable.

Example 1: Write each expression as a mathematical expression.

 Phrase Expression the amount of nine and eight 9 + 8 the amount of nine and also a number x 9 + x

The expression 9 + 8 represents a single number (17). This expression is a numerical expression, (likewise referred to as an arithmetic expression). The expression 9 + x represents a value that deserve to adjust. If x is 2, then the expression 9 + x has actually a worth of 11. If x is 6, then the expression has a worth of 15. So 9 + x is an algebraic expression. In the following few examples, we will certainly be functioning exclusively via algebraic expressions.

Example 2: Write each phrase as an algebraic expression.

 Phrase Expression nine increased by a number x 9 + x fourteenager lessened by a number p 14 - p salso less than a number t t - 7 the product of 9 and also a number n 9 · n or 9n thirty-2 split by a number y 32 ÷ y or In Example 2, each algebraic expression consisted of one number, one procedure and one variable. Let"s look at an example in which the expression consists of more than one number and/or operation.

Example 3: Write each phrase as an algebraic expression using the variable n.

 Phrase Expression five even more than twice a number 2n + 5 the product of a number and 6 6n salso separated by twice a number 7 ÷ 2n or three times a number diminished by 11 3n - 11 Example 4: A tiny agency has \$1000 to distribute to its employees as a bonus. How a lot money will each employee get?

Solution: Let e recurrent the number of employees in the agency. The amount of money each employee will obtain is stood for by the following algebraic expression:  Example 5: An electrician charges \$45 per hour and spends \$20 a day on gasoline. Write an algebraic expression to recurrent his revenue for someday.

Solution: Let x represent the number of hours the electrician works in at some point. The electrician"s revenue deserve to be stood for by the adhering to algebraic expression:

Solution: 45x - 20

Summary: A variable is a symbol supplied to reexisting a number in an expression or an equation. The value of this number have the right to change. An algebraic expression is a mathematical expression that is composed of variables, numbers and operations. The worth of this expression have the right to adjust.

### Exercises

Directions: Choose the algebraic expression that properly represents the phrase provided. Select your answer by clicking its button. Feedback to your answer is provided in the RESULTS BOX. If you make a mistake, choose a various switch.

 1. Fifteenager less than twice a number 15 - 2x2x + 152x - 15Namong the over.RESULTS BOX:
 2. Three times a number, boosted by seventeen 3(a + 17)3a + 17(17 + 3)aNone of the over.RESULTS BOX:
 3. The product of nine and also a number, lessened by six 9(m - 6)6(9 - m)9m - 6None of the above.RESULTS BOX:
 4. Thirty divided by seven times a number 30 + 7n 30(7n) Namong the above.See more: What Is The Electron Configuration For Arsenic ? Arsenic » Properties Of Free Atoms
 RESULTS BOX:
 5. Jenny earns \$30 a day functioning component time at a supersector. Write an algebraic expression to reexisting the amount of money she will earn in d days. 30d 30 + d None of the above
 RESULTS BOX: