Advanced MathMediumConstant in a grouped factorisation
Advanced Math practice question
For all x, x(x + 3) − 2(x + 3) = (x + 3)(x − k). What is the value of k?
Answer: 2
Both terms share (x + 3): (x + 3)(x − 2). So k = 2.
Common wrong answers
- If you answered 3
- 3 is the constant in the shared factor.
- If you answered 6
- 6 multiplies 2 by 3.
- If you answered -2
- −2 would give (x + 2), the wrong sign.
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