Write An Algebraic Expression For 8.9 Times A Number.Which Would You Simplify In Order To Evaluate The Expression When The Value Of The Variable Is 2?A. $8.9 \div 2$B. $8.9 + 2$C. $8.9 \times 2$D. $(8.9)^2$

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What is an Algebraic Expression?

An algebraic expression is a mathematical expression that consists of variables, constants, and mathematical operations. It is a way to represent a mathematical relationship between variables and constants using symbols and mathematical operations. Algebraic expressions are used to solve equations and inequalities, and they are a fundamental concept in mathematics.

Writing an Algebraic Expression for "8.9 Times a Number"

To write an algebraic expression for "8.9 times a number," we need to use the multiplication symbol (×) to represent the operation of multiplication. Let's call the number "x." The algebraic expression would be:

8.9 × x

This expression represents the operation of multiplying 8.9 by a number (x).

Simplifying the Expression

To simplify the expression, we need to evaluate the expression when the value of the variable (x) is 2. To do this, we need to substitute the value of x into the expression and perform the necessary calculations.

Evaluating the Expression

Let's evaluate the expression 8.9 × x when x = 2.

8.9 × 2 = 17.8

So, the value of the expression when x = 2 is 17.8.

Which Option is Correct?

Now, let's look at the options and determine which one is correct.

A. 8.9÷28.9 \div 2 B. 8.9+28.9 + 2 C. 8.9×28.9 \times 2 D. (8.9)2(8.9)^2

Option A is incorrect because it represents the operation of division, not multiplication.

Option B is incorrect because it represents the operation of addition, not multiplication.

Option C is correct because it represents the operation of multiplication, which is what we need to evaluate the expression.

Option D is incorrect because it represents the operation of exponentiation, not multiplication.

Conclusion

In conclusion, the correct option is C. 8.9×28.9 \times 2. This option represents the operation of multiplication, which is what we need to evaluate the expression when the value of the variable (x) is 2.

What is an Algebraic Expression?

An algebraic expression is a mathematical expression that consists of variables, constants, and mathematical operations. It is a way to represent a mathematical relationship between variables and constants using symbols and mathematical operations. Algebraic expressions are used to solve equations and inequalities, and they are a fundamental concept in mathematics.

Writing an Algebraic Expression for "8.9 Times a Number"

To write an algebraic expression for "8.9 times a number," we need to use the multiplication symbol (×) to represent the operation of multiplication. Let's call the number "x." The algebraic expression would be:

8.9 × x

This expression represents the operation of multiplying 8.9 by a number (x).

Simplifying the Expression

To simplify the expression, we need to evaluate the expression when the value of the variable (x) is 2. To do this, we need to substitute the value of x into the expression and perform the necessary calculations.

Evaluating the Expression

Let's evaluate the expression 8.9 × x when x = 2.

8.9 × 2 = 17.8

So, the value of the expression when x = 2 is 17.8.

Which Option is Correct?

Now, let's look at the options and determine which one is correct.

A. 8.9÷28.9 \div 2 B. 8.9+28.9 + 2 C. 8.9×28.9 \times 2 D. (8.9)2(8.9)^2

Option A is incorrect because it represents the operation of division, not multiplication.

Option B is incorrect because it represents the operation of addition, not multiplication.

Option C is correct because it represents the operation of multiplication, which is what we need to evaluate the expression.

Option D is incorrect because it represents the operation of exponentiation, not multiplication.

Conclusion

In conclusion, the correct option is C. 8.9×28.9 \times 2. This option represents the operation of multiplication, which is what we need to evaluate the expression when the value of the variable (x) is 2.

Algebraic Expressions: A Real-World Example

Algebraic expressions are used in many real-world applications, such as science, engineering, and economics. For example, in physics, algebraic expressions are used to describe the motion of objects, such as the trajectory of a projectile.

Tips for Working with Algebraic Expressions

Here are some tips for working with algebraic expressions:

  • Use variables to represent unknown values.
  • Use mathematical operations to represent relationships between variables and constants.
  • Simplify expressions by combining like terms.
  • Evaluate expressions by substituting values into the expression and performing the necessary calculations.

Common Algebraic Expressions

Here are some common algebraic expressions:

  • 2x + 3
  • x^2 + 4x + 4
  • 3x - 2
  • x/2 + 1

Conclusion

Q: What is an algebraic expression?

A: An algebraic expression is a mathematical expression that consists of variables, constants, and mathematical operations. It is a way to represent a mathematical relationship between variables and constants using symbols and mathematical operations.

Q: How do I write an algebraic expression for a given problem?

A: To write an algebraic expression for a given problem, you need to identify the variables, constants, and mathematical operations involved. For example, if the problem is "8.9 times a number," you would write the algebraic expression as 8.9 × x.

Q: What is the difference between an algebraic expression and an equation?

A: An algebraic expression is a mathematical expression that consists of variables, constants, and mathematical operations, while an equation is a statement that says two expressions are equal. For example, the algebraic expression 2x + 3 is different from the equation 2x + 3 = 5.

Q: How do I simplify an algebraic expression?

A: To simplify an algebraic expression, you need to combine like terms and perform the necessary calculations. For example, the expression 2x + 3 + 2x can be simplified to 4x + 3.

Q: What is the order of operations in algebraic expressions?

A: The order of operations in algebraic expressions is:

  1. Parentheses: Evaluate expressions inside parentheses first.
  2. Exponents: Evaluate any exponential expressions next.
  3. Multiplication and Division: Evaluate any multiplication and division operations from left to right.
  4. Addition and Subtraction: Finally, evaluate any addition and subtraction operations from left to right.

Q: How do I evaluate an algebraic expression?

A: To evaluate an algebraic expression, you need to substitute the values of the variables into the expression and perform the necessary calculations. For example, if the expression is 2x + 3 and x = 2, you would substitute x = 2 into the expression and get 2(2) + 3 = 7.

Q: What are some common algebraic expressions?

A: Some common algebraic expressions include:

  • 2x + 3
  • x^2 + 4x + 4
  • 3x - 2
  • x/2 + 1

Q: How do I use algebraic expressions in real-world applications?

A: Algebraic expressions are used in many real-world applications, such as science, engineering, and economics. For example, in physics, algebraic expressions are used to describe the motion of objects, such as the trajectory of a projectile.

Q: What are some tips for working with algebraic expressions?

A: Here are some tips for working with algebraic expressions:

  • Use variables to represent unknown values.
  • Use mathematical operations to represent relationships between variables and constants.
  • Simplify expressions by combining like terms.
  • Evaluate expressions by substituting values into the expression and performing the necessary calculations.

Conclusion

In conclusion, algebraic expressions are a fundamental concept in mathematics. They are used to represent mathematical relationships between variables and constants using symbols and mathematical operations. By understanding how to write and simplify algebraic expressions, we can solve equations and inequalities, and apply mathematical concepts to real-world problems.

Algebraic Expressions: A Real-World Example

Algebraic expressions are used in many real-world applications, such as science, engineering, and economics. For example, in physics, algebraic expressions are used to describe the motion of objects, such as the trajectory of a projectile.

Tips for Working with Algebraic Expressions

Here are some tips for working with algebraic expressions:

  • Use variables to represent unknown values.
  • Use mathematical operations to represent relationships between variables and constants.
  • Simplify expressions by combining like terms.
  • Evaluate expressions by substituting values into the expression and performing the necessary calculations.

Common Algebraic Expressions

Here are some common algebraic expressions:

  • 2x + 3
  • x^2 + 4x + 4
  • 3x - 2
  • x/2 + 1

Conclusion

In conclusion, algebraic expressions are a fundamental concept in mathematics. They are used to represent mathematical relationships between variables and constants using symbols and mathematical operations. By understanding how to write and simplify algebraic expressions, we can solve equations and inequalities, and apply mathematical concepts to real-world problems.