Question

Factorise 3x²+4x-39 completely.

Answer 1

${3x}^{2} + 4x - 39$

${3x}^{2} + 13x - 9x - 39$

$x(3x + 13) - 3(3x + 13)$

$(3x + 13)(x - 3)$

hope it helps you.........

Answer 2

${\large{\overbrace{\underbrace{\orange{your \: answer: (x + 3)(3x - 13)}}}}} \\ \red♡ dear *----*$

$\bf\red{ \underline{ using \: splitting \: the \: middle \: term \: method}}$

$\huge\ {3x}^{2} - 4x - 39 = 0\\ \\ \bf\ \implies: {3x}^{2} - (13x - 9x) - 39 = 0\\ \\ \bf\ \implies: {3x}^{2} - 13x + 9x - 39 = 0 \\ \\ \bf\ \implies: x(3x - 13) + 3(3x - 13) = 0 \\ \\ \bf\boxed{ \implies: (x + 3)(3x - 13) = 0 }\\ \\ \\ \bf\red{ \mapsto \: x + 3 = 0 }\\ \\ \bf\red{ \implies\: x = - 3} \\ \\ \bf\purple{ \mapsto3x + 13 = 0} \\ \\ \bf\purple{ \implies \: x = \frac{ - 13}{3} }$

$\large\boxed{ \fcolorbox{lime}{yellow}{hope \: it \: help \: you}}$