Question

help me very important questions

Answer 1

$2) \: \: \: 3x {}^{2} - x - 4 \\ \\ \: \: = 3x {}^{2} -x (4 - 3) - 4 \\ \\ \: \: = 3x {}^{2} - 4x + 3 x- 4 \\ \\ \: \: = x(3x - 4) + 1(3x - 4) \\ \\ \: \: = (3x - 4)(x + 1)$