Question

factors of polynomial 7 x square - 12 x minus 4 and hence find the values of x for which the polynomial has the value 0

Answer 1

${7x}^{2} - 12x - 4$

$= 7x^{2} - (14 - 2)x - 4$

$= {7x}^{2} - 14x + 2x - 4$

$= 7x(x - 2) + 2(x - 2)$

$= (x - 2)(7x + 2)$


Hence,

$value \: of \: x=(2)\: and \: (\frac{ - 2}{7} )$