Question

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Answer 1

Answer:

$(x-3)^2 =21$

Step-by-step explanation:

$~~~~~~~x^2-6x-12=0\\\\\implies x^2 -6x +9-21=0 \\\\\implies x^2 -2\cdot x \cdot 3 +3^2=21\\\\\implies (x-3)^2 =21$