Question

-14 = n/2 (2(6-2n)+(n-1)2)​

Answer 1

Answer:

-14 = n/2 (2(6-2n)+(n-1)2)

-14=n/2×2(6-2n+n-1)

-14=n(5-n)

-14=5n-n²

n²-5n=14

n²-5n-14=0

n²-7n+2n-14=0

n(n-7)+2(n-7)=0

(n-7) (n+2)=0

n-7=0,or,n+2=0

n=7,or,n=-2 (impossible)

Therefore, the answer is 7.

Answer 2

Step-by-step explanation:

$- 14 = \frac{n}{2} (2(6 - 2n) + (n - 1)2) \\ ⇒ - 14 = \frac{n}{2} (12 - 4n + 2n - 2) \\ ⇒ - 28 = 12n - 4n {}^{2} + 2 {n}^{2} - 2n \\ ⇒ - 28 = 10n - 2n {}^{2} \\ ⇒ - 28 = 2n(5 - n) \\ ⇒ - 2n = 5 - n + 28 \\ ⇒ - 2n = 33 - n \\ ⇒ 33 = - n + 2n \\ ⇒33 = n$

Hence:- N=33..is the correct answer..