Question

IF x²-x-42=(x+k)(x+6)​ then find k

Answer 1

Answer:-

Given,

$\sf {x}^{2} - x - 42 = (x + k)(x + 6)$

We have to find the value of k.

Now,

$\sf {x}^{2} - x - 42 = (x + k)(x + 6)$

$\sf \implies {x}^{2} - 7x + 6x - 42 =(x + k)(x + 6)$

$\sf \implies x(x - 7)+ 6(x - 7)=(x + k)(x + 6)$

$\sf \implies (x + 6)(x - 7)=(x + k)(x + 6)$

$\sf \implies (x - 7)=(x + k)$

$\sf \implies k = - 7$

Hence, the value of k is -7.

Answer 2

Answer:

Answer

Given,

x-x-42 = (x +k)(x +6)

We have to find the value of k.

Now,

x-X-42 (x +k)(x +6)

*-7x+6x 6x - 42 = (x +k)(x +6)

x(x -7)+6(x - 7) = (x+ k){x + 6)

(x+6)(x -7) = (x +k)(x +6)

Explanation:

(x+6)(x - 7) = (x +k)(x +6)

(x- 7) = (x +k)

k= -7

Hence, the value of k is -7.