Question:y gt |x - 3|For which of the following tables are all the values of x and their corresponding values...
GMAT Algebra : (Alg) Questions
\(\mathrm{y \gt |x - 3|}\)
For which of the following tables are all the values of x and their corresponding values of y solutions to the given inequality?
x y 1 3 3 1 5 3 x y 1 2 3 1 5 3 x y 1 3 3 0 5 4 x y 1 4 3 2 5 1
| x | y |
|---|---|
| 1 | 3 |
| 3 | 1 |
| 5 | 3 |
| x | y |
|---|---|
| 1 | 2 |
| 3 | 1 |
| 5 | 3 |
| x | y |
|---|---|
| 1 | 3 |
| 3 | 0 |
| 5 | 4 |
| x | y |
|---|---|
| 1 | 4 |
| 3 | 2 |
| 5 | 1 |
1. TRANSLATE the inequality into a checking process
- Given inequality: \(\mathrm{y \gt |x - 3|}\)
- Task: Find the table where ALL coordinate pairs (x, y) satisfy this inequality
- This means: For every row, the y-value must be strictly greater than \(\mathrm{|x - 3|}\)
2. SIMPLIFY by checking each table systematically
I'll evaluate \(\mathrm{|x - 3|}\) for each x-value and compare with the corresponding y-value.
Checking Table A:
- When x = 1: \(\mathrm{|1 - 3| = |-2| = 2}\), and y = 3. Since \(\mathrm{3 \gt 2}\) ✓
- When x = 3: \(\mathrm{|3 - 3| = |0| = 0}\), and y = 1. Since \(\mathrm{1 \gt 0}\) ✓
- When x = 5: \(\mathrm{|5 - 3| = |2| = 2}\), and y = 3. Since \(\mathrm{3 \gt 2}\) ✓
All three pairs work!
Checking Table B:
- When x = 1: \(\mathrm{|1 - 3| = 2}\), and y = 2. Since \(\mathrm{2 \gt 2}\)? No! \(\mathrm{2 = 2}\) ✗
Table B fails immediately.
Checking Table C:
- When x = 1: \(\mathrm{|1 - 3| = 2}\), and y = 3. Since \(\mathrm{3 \gt 2}\) ✓
- When x = 3: \(\mathrm{|3 - 3| = 0}\), and y = 0. Since \(\mathrm{0 \gt 0}\)? No! \(\mathrm{0 = 0}\) ✗
Table C fails at the second pair.
Checking Table D:
- When x = 1: \(\mathrm{|1 - 3| = 2}\), and y = 4. Since \(\mathrm{4 \gt 2}\) ✓
- When x = 3: \(\mathrm{|3 - 3| = 0}\), and y = 2. Since \(\mathrm{2 \gt 0}\) ✓
- When x = 5: \(\mathrm{|5 - 3| = 2}\), and y = 1. Since \(\mathrm{1 \gt 2}\)? No! \(\mathrm{1 \lt 2}\) ✗
Table D fails at the third pair.
3. APPLY CONSTRAINTS to select the final answer
Only Table A satisfies the strict inequality for all coordinate pairs.
Answer: A
Why Students Usually Falter on This Problem
Most Common Error Path:
Weak APPLY CONSTRAINTS skill: Students confuse > with ≥, thinking that \(\mathrm{y = |x - 3|}\) satisfies the inequality.
For example, in Table B when x = 1, they see \(\mathrm{|1 - 3| = 2}\) and y = 2, and incorrectly think "2 equals 2, so that works." They miss that the inequality requires y to be strictly greater than \(\mathrm{|x - 3|}\), not equal to it.
This may lead them to select Choice B or get confused when multiple tables seem to "work."
Second Most Common Error:
Poor SIMPLIFY execution: Students make arithmetic errors when computing absolute values, especially with negative results inside the absolute value bars.
For instance, they might calculate \(\mathrm{|1 - 3| = -2}\) instead of \(\mathrm{|-2| = 2}\), leading to incorrect comparisons throughout their checking process.
This leads to confusion and guessing among the answer choices.
The Bottom Line:
This problem tests whether students understand that inequalities require precise boundary conditions - "greater than" means the boundary itself doesn't count. The absolute value computation is straightforward, but the strict inequality comparison is where many students stumble.
| x | y |
|---|---|
| 1 | 3 |
| 3 | 1 |
| 5 | 3 |
| x | y |
|---|---|
| 1 | 2 |
| 3 | 1 |
| 5 | 3 |
| x | y |
|---|---|
| 1 | 3 |
| 3 | 0 |
| 5 | 4 |
| x | y |
|---|---|
| 1 | 4 |
| 3 | 2 |
| 5 | 1 |