SOLUTION: The Robinsons wish to increase the area of their 8-by-6 foot garden by 6 times the current amount. To do this they have decided to add the same amount to each side of the garden. H

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Question 600274: The Robinsons wish to increase the area of their 8-by-6 foot garden by 6 times the current amount. To do this they have decided to add the same amount to each side of the garden. How much should be added to each side of the garden?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
The Robinsons wish to increase the area of their 8-by-6 foot garden by 6 times the current amount.
To do this they have decided to add the same amount to each side of the garden.
How much should be added to each side of the garden?
:
Find the present area: 8 * 6 = 48 sq/ft
Find the increase of 6 times old area: 6 * 48 = 288 sq/ft
resulting total area: 48 + 288 = 336 sq/ft
:
Let x = amt added to each dimension to accomplish this
(x+6)*(x+8) = 336
FOIL
x^2 + 8x + 6x + 48 = 336
x^2 + 14x + 48 - 336 = 0
x^2 + 14x - 288 = 0
use the quadratic formula to find x
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
In this problem: a=1; b=14; c=-288
x+=+%28-14+%2B-+sqrt%2814%5E2-4%2Aa%2A-288+%29%29%2F%282%2A1%29+
you can do the math here: I got a positive solution of x ~ 11.36 ft