Question

factorize with suitable grouping
(9x)
$9x {}^{2} + 42x + 49 - 84$

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Answer 1

Step-by-step explanation:

$\longmapsto\sf 9 x{}^{2} + 42x + 49 - 84 \\\\ \longmapsto\sf (3x) {}^{2} + 2 \times 3x \times 7 + 7 {}^{2} - 84 \\\\\\ \star\sf a^2 + 2ab + b^2 = (a + b)^2 \\\\\\ \longmapsto\bold{ (3x + 7) {}^{2} - 84}\qquad [Required \ answer]$