Question 240 of 480
Find the range of values of x for which 7x - 3 > 25 + 3x
- A. x >7
- B. x<7
- C. x>-7
- D. x<-7
Correct Answer:
A
Explanation
To solve the inequality \( 7x - 3 > 25 + 3x \), we will follow a step-by-step approach to isolate \( x \) and determine the range of values that satisfy the inequality.
### Step 1: Rearranging the Inequality
We start with the original inequality:
\[
7x - 3 > 25 + 3x
\]
Our goal is to get all terms involving \( x \) on one side and constant terms on the other side. To do this, we can subtract \( 3x \) from both sides:
\[
7x - 3x - 3 > 25
\]
This simplifies to:
\[
4x - 3 > 25
\]
### Step 2: Isolating \( x \)
Next, we need to isolate \( 4x \). We can do this by adding \( 3 \) to both sides of the inequality:
\[
4x > 25 + 3
\]
This simplifies to:
\[
4x > 28
\]
Now, we divide both sides by \( 4 \) to solve for \( x \):
\[
x > \frac{28}{4}
\]
Calculating the right side gives us:
\[
x > 7
\]
### Conclusion
The solution to the inequality \( 7x - 3 > 25 + 3x \) is:
\[
x > 7
\]
Thus, the correct option is **A. x > 7**.
### Explanation of Other Options
Now, let's analyze the other options to understand why they are incorrect:
- **B. x < 7**: This option suggests that \( x \) is less than \( 7 \). However, our solution indicates that \( x \) must be greater than \( 7 \). Therefore, this option is incorrect.
- **C. x > -7**: This option states that \( x \) is greater than \( -7 \). While this is true for many values of \( x \), it does not satisfy the specific condition we derived from the inequality, which requires \( x \) to be greater than \( 7 \). Thus, this option is too broad and incorrect.
- **D. x < -7**: This option suggests that \( x \) is less than \( -7 \). This is not consistent with our solution, which requires \( x \) to be greater than \( 7 \). Therefore, this option is also incorrect.
### Summary of Key Points
- To solve the inequality \( 7x - 3 > 25 + 3x \), we rearranged the terms to isolate \( x \).
- We simplified the inequality step-by-step, leading to the conclusion that \( x > 7 \).
- The correct answer is **A. x > 7**.
- The other options are incorrect because they do not satisfy the derived condition from the inequality.
### Revision Summary
- Rearrange the inequality to isolate \( x \).
- Perform operations carefully to maintain the inequality's direction.
- Check each option against the derived solution to confirm correctness.
- Remember that inequalities can have strict (>) or non-strict (≥) conditions, affecting the solution set.