Q. 3

1. $x(3x + 2) - (2x + 4) \Rightarrow 3x^2 + 2x - 2x - 4 \Rightarrow 3x^2 - 0x - 4 \Rightarrow 3x^2 - 4$
2. $\frac{(ax^2 - x^2)}{(ax - x)} \Rightarrow \frac{x(ax - x)}{ax - x} \Rightarrow x$
$7x^2 - 63 \Rightarrow 7x^2 - 21x + 21x - 63 \Rightarrow 7x(x - 3) + 21 (x - 3) \Rightarrow (7x + 21)(x - 3) \Rightarrow 7(x + 3)(x - 3)$