Question

$x {?}^{2} - 81$
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Answer 1

Answer:

${x}^{2} - 81 \\ \\ = ( {x})^{2} - {(9})^{2} \\ \\ = (x + 9)(x - 9) \\ \\ either \: x + 9 = 0 \\ \\ = > x = - 9 \\ \\ or \: x - 9 = 0 \\ \\ = > x = 9 \\ \\ formula \: used \: \\ \\ {a}^{2} - {b}^{2} \\ \\ = (a + b)(a - b)$

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Answer 2

Answer:

77788+788879+78788

788+6788+78