How do you solve $- 7 n - 2 n = 5 + 1 - n - 7 n$ $-7n - 2n = 5+ 1- n - 7n$ ?

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Answer 1 · 2017-10-25T19:32:22

$n = - 6$ $n=-6$

I'll try to do it step by step

$- 7 n - 2 n = 5 + 1 - n - 7 n$ $-7n-2n=5+1-n-7n$

adding the $n$ $n$ 's and the numbers in each side

$- 9 n = 6 - 8 n$ $-9n=6-8n$

the $- 8 n$ $-8n$ goes to the other side as $+ 8 n$ $+8n$

$- 9 n + 8 n = 6$ $-9n+8n=6$

then we add the $n$ $n$ 's in the left hand side

$- n = 6$ $-n = 6$

multiplying in both sides by $(- 1)$ $(-1)$

$(- 1) \cdot (- n) = (- 1) \cdot 6$ $(-1)·(-n)=(-1)·6$

and finally

$n = - 6$ $n=-6$

To prove we are right we change $n$ $n$ into $- 6$ $-6$ in the original ecuation.

$(- 7) \cdot (- 6) - 2 \cdot (- 6) = 5 + 1 - (- 6) - 7 \cdot (- 6)$ $(-7)·(-6) - 2·(-6) =5+1 -(-6)-7·(-6)$

and we get $36 + 12 = 6 + 6 + 36$ $36+12=6+6+36$ $\Rightarrow$ $=>$ $48 = 48$ $48=48$

Since we get the equalty is true, the answer is correct.

How do you solve −7n−2n=5+1−n−7n-7n - 2n = 5+ 1- n - 7n?