Question

${3x}^{2} + 6x - 144$
​

Answer 1

Answer:

x = -8, 6

Step-by-step explanation:

$3x^2 + 6x - 144 = 0\\\\\\= 3(x^2 + 2x - 48) = 0\\\\\\\implies x^2 + 2x - 48 = 0\\\\\\\text{Using quadratic formula,}\\\\\\x = \dfrac{-b \pm \sqrt{b^2 - 4ac}}{2a}\\\\\\= \dfrac{-2 \pm \sqrt{4 - 4(1)(-48)}}{2(1)}\\\\\\= \dfrac{-2 \pm \sqrt{4 + 192}}{2}\\\\\\= \dfrac{-2 \pm 14}{2}\\\\\\\therefore \: x = \dfrac{-2 - 14}{2} \: or \: \dfrac{-2 + 14}{2}\\\\\\= \dfrac{-16}{2} \: or \: \dfrac{12}{2}\\\\\\= -8 \: or \: 6$

x = -8, 6

Answer 2

$\mathfrak{\blue{\underline{\underline{Question}}}}$

Solve:

${3x}^{2} + 6x - 144$

$\mathfrak{\blue{\underline{\underline{Answer}}}}$

$\boxed{\boxed{ x = -8} \boxed{ x = 6}}$

$\mathfrak{\blue{\underline{\underline{Step\: By\: Step\: Solution}}}}$

To factorize p(x)

p(x) = 0

$p(x) = {3x}^{2} + 6x - 144 = 0$

Taking out like term

$\implies {x}^{2} + 2x - 48 = 0$

By middle term splitting

$\implies x^{2} - 6x + 8x - 48 = 0 \\ \implies x(x - 6) + 8(x - 6) = 0 \\ \implies (x + 8)(x - 6) = 0$

x + 8 = 0

x = -8

x - 6 = 0

x = 6