SOLUTION: one of the roots of the equation x^2+3 x-18 = 0 is 3. what is the other root?

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Question 439842: one of the roots of the equation x^2+3 x-18 = 0 is 3. what is the other root?
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
simply -18%2F3=-6
let's see it:
x%5E2+%2B+3x+-+18+=+0
Because you have a quadratic with leading coefficient 1, you can factored it as %28x-a%29%28x+-+b%29, and a, b are the two roots.
x%5E2+-3x+%2B+6x+-+18+=+0
x%28x%5E2+-3%29+%2B+6%28x+-+3%29+=+0
%28x+-+3%29%28x+%2B+6%29+=+0
roots:
x+=+3 or x=-6