Advanced MathEasy–MediumFactor of a difference of squares
Advanced Math practice question
The expression x² − 16 can be written as (x + 4)(x − k), where k is a positive constant. What is the value of k?
Answer: 4
x² − 16 = (x + 4)(x − 4).
Common wrong answers
- If you answered 8
- 8 is 16 ÷ 2.
- If you answered 16
- 16 is the constant term, not its square root.
- If you answered -4
- The question asks for the positive constant k in (x − k).
More Advanced Math questions
- Easy–Medium
If f(x) = 2x² − 3, what is f(4)? - Easy–Medium
Which expression is equivalent to (2x³)(3x⁴)? - Easy–Medium
What are the solutions to x² − 16 = 0? - Easy–Medium
Which expression is equivalent to (x + 5)²? - Easy–Medium
For x ≠ 0, which expression is equivalent to (x² + 3x) / x? - Easy–Medium
What are the solutions to the equation 2(x − 3)² − 32 = 0 ?
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