Advanced MathHardConstant in a simplified quotient
Advanced Math practice question
For x ≠ 0 and x ≠ −5, (x² − 25)/(x² + 5x) is equivalent to (x − k)/x, where k is a constant. What is the value of k?
Answer: 5
(x − 5)(x + 5) over x(x + 5): cancel (x + 5) to get (x − 5)/x. So k = 5.
Common wrong answers
- If you answered 0
- 0 would make the expression equal 1, which is false.
- If you answered 25
- 25 is the constant before factoring.
- If you answered -5
- −5 would give (x + 5)/x, the cancelled factor.
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