SOLUTION: I need to find the excluded variables for this expression= (y^2+5y-6)/(y^2-8y+7) I've already simplified it into (y+6)/(y-7) but i'm having trouble finding the excluded variables

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Question 517523: I need to find the excluded variables for this expression= (y^2+5y-6)/(y^2-8y+7) I've already simplified it into (y+6)/(y-7) but i'm having trouble finding the excluded variables
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
excluded values are those which result in undefined results (usually, division by zero)

if y = 7, then your simplified denominator is zero ___ this is excluded

even though you canceled the y-1 factors, y = 1 is an excluded value because there is a "hole" in the graph there