Question

FACTORISE : (x+2y)2-11(x+2y)-42​

Answer 1

Answer:

$(x + 2y - 7)(x + 2y + 6).$

Step-by-step explanation:

$let \: (x + 2y) = z \\ \\ {z}^{2} - 11z - 42 \\ \\ {z}^{2} + 6z - 7z - 42 \\ \\ z(z + 6) - 7(z + 6) \\ \\ (z - 7)(z + 6) \\ \\ (x + 2y - 7)(x + 2y + 6).$