Question

Factorise :
$7\sqrt{2}{x}^2-10x-4\sqrt{2}$

Answer 1

$7\sqrt{2}{x}^2-10x-4\sqrt{2}$

$7\sqrt{2}\times 4\sqrt{2}=56=14\times 64$

$(14-4)=10$

so, we split 10 as (14-4)

$\Rightarrow 7\sqrt{2}{x}^2-(14-4)x-4\sqrt{2}$

$\Rightarrow 7\sqrt{2}{x}^2-14x+4x-4\sqrt{2}$

$\Rightarrow 7\sqrt{2}x[x-\sqrt{2}]+4[x-\sqrt{2}]$

$\Rightarrow [7\sqrt{2}x+4][x-\sqrt{2}]$