Question

a
${a }^{2} - {b}^{2} - 4ac + 4 {c}^{2}$

Answer 1

Hi friend, Harish here.

Here is your answer.

$a^2 - b^2 - 4ac + 4c^2 \\ \\ \to \bigl (a^2 -4ac +4c^2 \bigr) - b^2 \\ \\ \to (a-2c)^2 -b^2 \\ \\ \to (a-2c -b) (a-2c +b)$
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Hope my answer is helpful to you.