SOLUTION: estimate the roots of the equation: y = x^2 - 2x - 8

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Question 389606: estimate the
roots of the equation: y = x^2 - 2x - 8
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi,         

Note: roots of an equation are found when y = 0

     x^2 - 2x - 8 = 0

  Factoring

(x-4)(x+2) = 0 Note:SUM of the inner product(-4x) and the outer product(2x) = -2x  

(x-4) = 0     x = 4

(x+2) = 0     x = -2