Algebraic expressions With instance Problems and also Interactive Exercises
Use the complying with examples and also interactive practice to learn about Writing Algebraic Expressions.
You are watching: Seven less than a number divided by 3 is five
Solution: Let g stand for the variety of groups in Ms. Jensen"s class.
Then 2 · g, or 2g can represent "g teams 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 supplied to stand for a number in one expression or one equation. The worth of this number can vary (change). Let"s watch at an example in i beg your pardon we use a variable.
Example 1: Write each expression as a mathematics 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, (also referred to as an arithmetic expression). The expression 9 + x represents a worth that have the right to change. If x is 2, then the expression 9 + x has a value of 11. If x is 6, climate the expression has a value of 15. So 9 + x is an algebraic expression. In the next couple of examples, we will certainly be working solely with algebraic expressions.
Example 2: Write each expression as one algebraic expression.
| Phrase | Expression |
| nine raised by a number x | 9 + x |
| fourteen reduced by a number p | 14 - p |
| seven much less than a number t | t - 7 |
| the product that 9 and also a number n | 9 · n or 9n |
| thirty-two split by a number y | 32 ÷ y or  |
In instance 2, every algebraic expression included one number, one operation and one variable. Let"s look at at an instance in i beg your pardon the expression consists of more than one number and/or operation.
Example 3: Write each expression as one algebraic expression making use of the change n.
| Phrase | Expression |
| five more than twice a number | 2n + 5 |
| the product of a number and also 6 | 6n |
| seven divided by twice a number | 7 ÷ 2n or  |
| three time a number diminished by 11 | 3n - 11 |
Solution: Let e represent the number of employees in the company. The quantity of money each employee will obtain is represented by the following algebraic expression:
Solution: Let x represent the number of hours the electrician functions in one day. The electrician"s earnings can be stood for by the adhering to algebraic expression:
Solution: 45x - 20
Summary: A variable is a symbol provided to represent a number in one expression or an equation. The worth of this number can change. An algebraic expression is a mathematical expression that is composed of variables, numbers and also operations. The value of this expression have the right to change.
Exercises
Directions: choose the algebraic expression that correctly represents the expression provided. Select your prize by clicking its button. Feedback to your answer is detailed in the outcomes BOX. If you make a mistake, choose a different button.
| 1. | Fifteen much less than twice a number |
| 15 - 2x2x + 152x - 15None that the above. RESULTS BOX: |
| 2. | Three time a number, raised by seventeen |
| 3(a + 17)3a + 17(17 + 3)aNone that the above. RESULTS BOX: |
| 3. | The product the nine and also a number, lessened by six |
| 9(m - 6)6(9 - m)9m - 6None the the above. RESULTS BOX: |
| 4. | Thirty split by 7 times a number | |
| 30 + 7n | ||
 | ||
| 30(7n) | ||
| None of the above. See more: What Does ' I Didnt Mean To Hurt You ' Really Mean? “I Didn'T Mean To Hurt You” |
| RESULTS BOX: |
| 5. | Jenny earns $30 a work working component time in ~ a supermarket. Compose an algebraic expression to represent the lot of money she will earn in d days. | |
| 30d | ||
 | ||
| 30 + d | ||
| None the the above |
| RESULTS BOX: |