SOLUTION: b is a point between ac if ab=6x and bc=x^2 and ac=27 find x

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Question 286471: b is a point between ac if ab=6x and bc=x^2 and ac=27 find x
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Since b is somewhere on ac, this means that ab%2Bbc=ac by the segment addition postulate (ie the parts of a line segment add up to the total line segment)

So 6x%2Bx%5E2=27 which then becomes x%5E2%2B6x-27=0. Factor to get %28x%2B9%29%28x-3%29=0. Now use the zero product property and solve to get x=-9 or x=3


Since we're dealing with lengths, the only sensible answer is x=3