Need an explanation solve |3 - x| = 8

|3−x|=8 

|−x+3|=8Solve Absolute Value.|−x+3|=8

We know either   −x+3=8 or−x+3=−8−x+3=8    (Possibility 1)   −x+3−3=8−3                      (Subtract 3 from both sides)−x=5−x−1=5−1  

        (Divide both sides by -1)   x=−5−x+3=−8   (Possibility 2)   −x+3−3=−8−3     (Subtract 3 from both sides)   −x=−11−x−1=−11−1                                                          (Divide both sides by -1)x=11x=−5 or x=11

(math papa) 

A) for the n row: 22+(n-1)×6therefore,b) 100-22=78that means (n-1)×6=7878÷6=1313+1=1414th row has 100 seats