Question

of x+2 is the factor of the polynomial 3x^2-kx then find the value of k​

Answer 1

$\huge{\underline{\underline{\bold{\blue{\mathtt{Question\::}}}}}}$

• $\bf{3x}^{2}\:-\:kx$

${ }$

$\huge{\underline{\underline{\bold{\blue{\mathtt{Find\::}}}}}}$

• $\bf{Value\:of\:K}$

${ }$

$\huge{\underline{\underline{\bold{\blue{\mathtt{Solution\::}}}}}}$

• $\boxed{\sf{\green{\bold{x\:+\:2}\:\Longrightarrow{\green{\bold{x=\:-\:2}}}}}}$

${ }$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\:\sf{(3x)}^{2}\:-\:kx$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\:\sf{(3\:\times\:-2)}^{2}\:{-\:k\:\times\:-2}$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\:\sf{3\:\times\:4\:+\:2k}$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\:\sf{12\:+\:2\:k}$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\:\sf{2k\:=\:-\:12}$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\:\sf{k\:={\frac{-\:12}{2}}}$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\:\sf{k\:=\:-\:6}$

${ }$

• $\therefore\:{\underline{\sf{Hence,\:the\:value\:of\:k\:is\:{\bold{-\:6}}}}}$

Answer 2

Question :-

• x + 2 is the factor of polynomial 3x² - kx then find the value of k.

Given equation :-

• 3x² -kx

To find :-

• Value of k.

Solution :-

• It is given in the question that x + 2 is the factor of 3x² - kx

ㅤ‎ㅤ‎ㅤ‎ㅤ‎ㅤ‎=> x + 2

ㅤ‎ㅤ‎ㅤ‎ㅤ‎=>ㅤ‎x = -2

Now, substituting the value of x in polynomial :-

• 3x² - kx = 0

• 3(-2)² - k(-2) = 0

• 3(4) + 2k = 0

• 12 + 2k = 0

• 2k = -12

• k = -12/2

• k = -6

Therefore , value of k = -6.