Question

25 a square minus 4 b square + 28 B C - 49 c square​

Answer 1

$25a{ }^{2} - 4b {}^{2} + 28bc - 49c \\ {(5a)}^{2} - ((2b) {}^{2} - 2.2b.7c + (7c) {}^{2} ) \\ (5a) {}^{2} - (2b - 7c) {}^{2} \\ (5a + 2b - 7c)(5a - 2b + 7c) \\ \\ hope \: it \: help \: you \:$