Classify the following as 'arithmetic expressions' or 'algebraic expressions'.
`5+7b-9`

Answer

To classify the expression `5 + 7b - 9`, we will follow these steps:

### Step 1: Understand the Definitions
- **Arithmetic Expression**: An arithmetic expression consists only of numbers (numerical values) and operations (like addition, subtraction, multiplication, and division). The result of an arithmetic expression is always a numerical value.
- **Algebraic Expression**: An algebraic expression includes numbers, variables (like x, y, b), and operations. The presence of at least one variable makes it an algebraic expression.

### Step 2: Analyze the Given Expression
The expression given is `5 + 7b - 9`.

### Step 3: Identify the Components
- The expression contains:
- Numerical values: 5 and -9
- A variable: b (which is multiplied by 7)

### Step 4: Classify the Expression
Since the expression includes both numerical values and a variable (b), it fits the definition of an algebraic expression.

### Conclusion
Therefore, the expression `5 + 7b - 9` is classified as an **algebraic expression**.

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