SOLUTION: Word Problem Two -A rectangular plot of ground measuring 12 meters by 20 meters is surrounded by a sidewalk of a uniform width. The area of the sidewalk is 68 square meters. Find

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Question 230898: Word Problem Two -A rectangular plot of ground measuring 12 meters by 20 meters is surrounded by a sidewalk of a uniform width. The area of the sidewalk is 68 square meters. Find the width of the walk.. (Show a complete algebraic solution for the problem and check the answer.)

I DREW A PICTURE THEN WAS LOST….
He said that you can possibly use quadratic equation but don’t have to..

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let the width of the walk = w
Then the area of the plot plus
the walk is:
%2812+%2B+2w%29%2A%2820+%2B+2w%29
The area of the plot is given as:
12%2A20+=+240 m2
The area of the walk is given as 68 m2
Thus, the area of the plot plus walk is
240+%2B+68+=+308, so
%2812+%2B+2w%29%2A%2820+%2B+2w%29+=+308
240+%2B+40w+%2B+24w+%2B+4w%5E2+=+308
4w%5E2+%2B+64w+%2B+240+-+308+=+0
4w%5E2+%2B+64w+-+68+=+0
w%5E2+%2B+16w+-+17+=+0
I can solve by completing the square
w%5E2+%2B+16w+%2B+%2816%2F2%29%5E2+=+17+%2B+%2816%2F2%29%5E2
w%5E2+%2B+16w+%2B+64+=+17+%2B+64
%28w+%2B+8%29%5E2+=+81
Take square root of both sides
w+%2B+8+=+9
w+=+1 m
The walk is 1 meter wide
check:
%2812+%2B+2w%29%2A%2820+%2B+2w%29+=+308
%2812+%2B+2%2A1%29%2A%2820+%2B+2%2A1%29+=+308
14%2A22+=+308
308+=+308
OK