Question 908699
{{{x^4-53x^2+196= (x^2-4)(x^2-49)}}}
{{{x^4-53x^2+196= (x-2)(x+2)(x-7)(x+7)}}}
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{{{7x^2-7=7(x^2-1)}}}
{{{7x^2-7=7(x-1)(x+1)}}}