Question:The function h is defined by \(\mathrm{h(x) = |x - 4| + 3}\). What is the value of \(\mathrm{h(1)}\)?0368
GMAT Algebra : (Alg) Questions
The function h is defined by \(\mathrm{h(x) = |x - 4| + 3}\). What is the value of \(\mathrm{h(1)}\)?
- 0
- 3
- 6
- 8
1. TRANSLATE the problem information
- Given information:
- Function: \(\mathrm{h(x) = |x - 4| + 3}\)
- Need to find: \(\mathrm{h(1)}\)
- This means substitute \(\mathrm{x = 1}\) into the function
2. TRANSLATE the substitution
- Replace every x in \(\mathrm{h(x) = |x - 4| + 3}\) with the value 1
- \(\mathrm{h(1) = |1 - 4| + 3}\)
3. SIMPLIFY inside the absolute value first
- Calculate \(\mathrm{1 - 4 = -3}\)
- \(\mathrm{h(1) = |-3| + 3}\)
4. SIMPLIFY by evaluating the absolute value
- Remember: absolute value gives the distance from zero
- \(\mathrm{|-3| = 3}\) (the distance from -3 to 0 is 3 units)
- \(\mathrm{h(1) = 3 + 3}\)
5. SIMPLIFY the final arithmetic
- \(\mathrm{h(1) = 3 + 3 = 6}\)
Answer: C (6)
Why Students Usually Falter on This Problem
Most Common Error Path:
Weak SIMPLIFY execution with absolute value: Students correctly substitute and get \(\mathrm{|-3| + 3}\), but then evaluate \(\mathrm{|-3|}\) as -3 instead of 3.
They think "the absolute value of negative 3 is still negative 3" instead of remembering that absolute value always gives a positive result (or zero). This gives them \(\mathrm{h(1) = -3 + 3 = 0}\).
This leads them to select Choice A (0).
Second Most Common Error:
Poor TRANSLATE reasoning: Students misunderstand what \(\mathrm{h(1)}\) means and try to solve \(\mathrm{|x - 4| + 3 = 1}\) instead of substituting \(\mathrm{x = 1}\) into the function.
This creates confusion about what they're supposed to be finding, leading to abandoning systematic solution and guessing.
The Bottom Line:
This problem tests whether students truly understand both function notation (what it means to evaluate a function at a specific value) and the definition of absolute value (always non-negative). The combination of these two concepts in one problem creates multiple opportunities for conceptual confusion.