How do you solve using the quadratic formula #x^2-7x-8=0#?

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Answer 1 · 2016-11-13T22:35:12

#x = 8# and #x = -1#

This quadratic can be factored to:

#(x - 8)(x + 1) = 0#

Solving for #(x - 8)# gives:

#((x - 8)(x + 1))/((x + 1)) = 0/(x + 1)#

#x - 8 = 0#

#x - 8 + 8 = 0 + 8#

#x = 8#

Solving for #(x + 1)# gives:

#((x - 8)(x + 1))/((x - 8)) = 0/(x - 8)#

#x + 1 = 0#

#x + 1 - 1 = 0 - 1#

#x = -1#