SOLUTION: Bob and Kevin both have square vegetable gardens. Kevin's garden is 10 feet longer than Bob's garden, and its area is four times the area of Bob's garden. What are the dimensions o

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Question 380165: Bob and Kevin both have square vegetable gardens. Kevin's garden is 10 feet longer than Bob's garden, and its area is four times the area of Bob's garden. What are the dimensions of Bob's garden?
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
Bob's garden -side length be x feet
Area = x*x=x^2
..
Kevin's garden - side length = x+10 feet
..
so area = (x+10)*(x+10)
=x^+20x+100
..
x^2+20x+100=4x^2
3x^2-20x-100=0
3x^2-30x+10x-100=0
3x(x-10)+10(x-10)=0
(x-10)(3x+10)=0
x= 10
Bob's garden dimensions = 10 feet by 10 feet
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m.ananth@hotmail.ca