Find the rule which gives the number of matchsticks required to make the following matchstick patterns. Use a variable to write the rule.
A pattern of letter U as `U`

Answer

To find the rule for the number of matchsticks required to create a pattern of the letter U using matchsticks, we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure of U**:
- The letter U can be visualized as having two vertical sides and one horizontal bottom.

2. **Count the Matchsticks for One U**:
- To create one U, we need:
- 2 vertical matchsticks (one for each side)
- 1 horizontal matchstick (for the bottom)
- Therefore, the total number of matchsticks required for one U is:
\[ 2 \text{ (vertical)} + 1 \text{ (horizontal)} = 3 \text{ matchsticks} \]

3. **Establish a Variable for the Number of Us**:
- Let \( n \) be the number of U's we want to create.

4. **Calculate the Total Number of Matchsticks**:
- If we want to make \( n \) U's, the total number of matchsticks required will be:
\[ \text{Total matchsticks} = 3 \times n \]

5. **Write the Rule**:
- The rule that gives the number of matchsticks required to make \( n \) U's is:
\[ \text{Total matchsticks} = 3n \]

### Final Rule:
The rule for the number of matchsticks required to create a pattern of U's is \( 3n \), where \( n \) is the number of U's.

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