Question 357 of 480
Simplify the expression \( 3(2x + 4) - 5(x - 2) \).
- \( x + 22 \)
- \( x + 10 \)
Correct Answer:
D
Explanation
To simplify the expression \( 3(2x + 4) - 5(x - 2) \), we will follow a step-by-step approach.
### Step 1: Distribute the constants
First, we need to distribute the constants outside the parentheses to the terms inside the parentheses.
1. For the first part, \( 3(2x + 4) \):
- Multiply \( 3 \) by \( 2x \):
\[
3 \times 2x = 6x
\]
- Multiply \( 3 \) by \( 4 \):
\[
3 \times 4 = 12
\]
- So, \( 3(2x + 4) = 6x + 12 \).
2. For the second part, \( -5(x - 2) \):
- Multiply \( -5 \) by \( x \):
\[
-5 \times x = -5x
\]
- Multiply \( -5 \) by \( -2 \):
\[
-5 \times -2 = 10
\]
- So, \( -5(x - 2) = -5x + 10 \).
### Step 2: Combine the results
Now we can combine the results from both distributions:
\[
6x + 12 - 5x + 10
\]
### Step 3: Combine like terms
Next, we will combine the like terms (the terms with \( x \) and the constant terms):
1. Combine the \( x \) terms:
\[
6x - 5x = 1x \quad \text{(or simply } x\text{)}
\]
2. Combine the constant terms:
\[
12 + 10 = 22
\]
### Final Result
Putting it all together, we have:
\[
x + 22
\]
### Conclusion
The simplified expression is \( x + 22 \).
### Answer
The correct option is **B. \( x + 22 \)**.
### Explanation of Other Options
- **Option A**: [blank] - This option does not provide any expression, so it cannot be correct.
- **Option C**: [blank] - Similar to Option A, this option is also blank and cannot be correct.
- **Option D**: \( x + 10 \) - This option is incorrect because we correctly calculated the constant term to be \( 22 \), not \( 10 \).
### Revision Summary
- Distribute constants to terms inside parentheses carefully.
- Combine like terms (both variable and constant terms) after distribution.
- Always double-check calculations to avoid simple arithmetic errors.
- The final simplified expression for \( 3(2x + 4) - 5(x - 2) \) is \( x + 22 \).