Advanced MathHardDifference of two squared monomials
Advanced Math practice question
For all values of x, (4x)² − (2x)² is equivalent to kx², where k is a constant. What is the value of k?
Answer: 12
(4x)² = 16x² and (2x)² = 4x², so the difference is 12x².
Common wrong answers
- If you answered 2
- 2 subtracts the coefficients without squaring.
- If you answered 4
- 4 squares the difference of the coefficients, (4 − 2)².
- If you answered 20
- 20 adds 16 and 4.
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