Algebraic expression With instance Problems and also Interactive Exercises

Use the adhering to examples and interactive exercises to learn about Writing Algebraic Expressions.

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Problem: Ms. Jensen likes to division her class into groups of 2. Usage mathematical signs to represent all the college student in she class.

Solution: Let g represent the variety of groups in Ms. Jensen"s class.

Then 2 · g, or 2g can represent "g groups of 2 students".

In the problem above, the change g to represent the variety of groups in Ms. Jensen"s class. A variable is a symbol used to represent a number in one expression or one equation. The value of this number deserve to vary (change). Let"s look at at an example in i beg your pardon we use a variable.

Example 1: Write each phrase as a math expression.

the amount of nine and eight9 + 8
the amount of nine and also a number x9 + x

The expression 9 + 8 represents a solitary number (17). This expression is a numerical expression, (also called an arithmetic expression). The expression 9 + x represents a worth that deserve to change. If x is 2, then the expression 9 + x has 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 next few examples, we will certainly be working exclusively with algebraic expressions.

Example 2: Write each phrase as an algebraic expression.

nine boosted by a number x9 + x
fourteen lessened by a number p14 - p
seven less than a number tt - 7
the product that 9 and also a number n· n or 9n
thirty-two separated by a number y32 ÷ y or

In example 2, each algebraic expression included one number, one operation and also one variable. Let"s look at at an instance in i beg your pardon the expression is composed of an ext than one number and/or operation.

Example 3: Write each expression as one algebraic expression utilizing the variable n.

five much more than double a number2n + 5
the product of a number and also 66n
seven split by twice a number÷ 2n or
three time a number diminished by 113n - 11

Example 4: A small company has actually $1000 to distribute to that employees as a bonus. How much money will certainly each employee get?

Solution: Let e represent the variety of employees in the company. The lot of money every employee will obtain is represented by the complying with algebraic expression:


Example 5: An electrician dues $45 per hour and also spends $20 a day on gasoline. Create an algebraic expression to stand for his earnings for one day.

Solution: Let x stand for the variety of hours the electrician works in one day. The electrician"s earnings have the right to be stood for by the following algebraic expression:

Solution: 45x - 20

Summary: A variable is a symbol used to represent a number in one expression or one equation. The worth of this number have the right to change. An algebraic expression is a mathematics expression that is composed of variables, numbers and also operations. The value of this expression can change.


Directions: select the algebraic expression that properly represents the phrase provided. Pick your prize by clicking its button. Feedback to her answer is listed in the outcomes BOX. If you make a mistake, choose a different button.

1. Fifteen much less than double a number 
 15 - 2x2x + 152x - 15None of the above.


2. Three time a number, raised by seventeen 
 3(a + 17)3a + 17(17 + 3)aNone that the above.


3. The product the nine and a number, reduced by six 
 9(m - 6)6(9 - m)9m - 6None the the above.


4. Thirty split by seven times a number 
 30 + 7n
None the the above.

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5. Jenny earns $30 a work working part time in ~ a supermarket. Create an algebraic expression to stand for the lot of money she will certainly earn in d days. 
30 + d
None that the above