Question

solve my this question plz
question is factorise

Answer 1

$(b). \: \: 36x {}^{2} - 84xy + 49y {}^{2} - 25z { }^{2} \\ \\ = (6x) {}^{2} - 2 \times 6x \times 7y + (7y) {}^{2} - 25z { }^{2} \\ \\ = > \: it \: forms \: the \: identity \: of \: \\ (x - y) {}^{2} = (x) {}^{2} + (y) {}^{2} - 2xy \\ \\ = (6x - 7y) {}^{2} - (5z) {}^{2} \\ \\ now \: \: it \: forms \: the \: identity \: of \: \\ (x) {}^{2} - (y) {}^{2} = (x + y)(x - y) \\ \\ = (6x - 7y - 5z)(6x - 7y + 5z) \\ \\ hence \: factorised. \\ \\ \\ please \: mark \: it \: as \: brainliest.$