SOLUTION: Please help me with solving this last home worl problem it is due tomorrow! Thank . Solve using the five-step problem-solving process. Show all steps necessary to arrive at your

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Question 302389: Please help me with solving this last home worl problem it is due tomorrow! Thank .
Solve using the five-step problem-solving process. Show all steps necessary to arrive at your solution.
A rectangular flower bed with width 12 feet and length 15 feet is going to have a walkway of uniform width on all sides. If the area of the walkway is 90 square feet, how wide is the walkway?
you.
Answer by london maths tutor(243) About Me  (Show Source):
You can put this solution on YOUR website!
Let's the walk way width be x
The width including walk way = 12 + x + x = 12 + 2x
The length including walk way = 15 + x + x = 15 + 2x
Area of the flower bed = 12*15 = 180 ft^2
Area of the flower bed and walk way = (12+2x)*(15+2x)
The difference of the two area is 90 ft^2
Therefore:
[(12+2x)*(15+2x)] - 180 = 90
(180 + 24x + 30x + 4x^2) - 180 = 90
4x^2 + 54x - 90 = 0
2x^2 + 27x - 45 = 0
Using the formular : x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
where a = 2 , b = 27 and c = -45
x = 1.5 ft or - 15ft(N/A)
Answer: The width of the path way is 1.5ft