SOLUTION: What are the values of r in the equation r2-7r-8=0

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Question 381630: What are the values of r in the equation r2-7r-8=0
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi,         

Solving for r

r^2-7r-8=0

Factoring

(r - 8)(r + 1)=0 Note:SUM of the inner product(-8r) and the outer product(1*r) = -7r

(r - 8)= 0

   r = 8

(r + 1)=0

   r = -1