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Answer: The answer should be 3.
Step-by-step explanation: You plug in 2 instead of X and that’s it. Then you calculate your equation, and receive your answer.
The square of a binomial expands as follows:

Expanding all the binomials, we have

Sum like terms:

Simplify terms appearing on both sides:

Move all terms involving k to the left and all numbers to the right:

Divide both sides by -20:

The answer to this message was because