SOLUTION: I am not good at all with word problems and needs help A rectangle garden is to be surrounded by a walkway of constant width. The gardens dimensions are 30 ft by 40 ft. The tota

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: I am not good at all with word problems and needs help A rectangle garden is to be surrounded by a walkway of constant width. The gardens dimensions are 30 ft by 40 ft. The tota      Log On


   

Question 93090: I am not good at all with word problems and needs help
A rectangle garden is to be surrounded by a walkway of constant width. The gardens dimensions are 30 ft by 40 ft. The total area, garden plus walkway, is to be 1800 ft^2
What must be the width of the walkway to the nearest thousandth?
Thank you
Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
30*40=1200 area of the garden.
1800=(30+2w)(40+2w) these are the dimentions of the garden plus the walk way.
1800=1200+80x+60w+4w^2
4w62+140w+1200-1800=0
4w^2+140w-600=0
4(w^2+35w-150)=0
using the quadratic equaton we get:
w=%28-b%2B-sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29
w=(-35+-sqrt[35^2-4*1*-150])/2*1
w=-35+-sqrt[1225+600])/2
w=(-35+-sqrt1825)/2
w=(-35+-42.72)/2
w=(-35+42.72)/2
w=7.72/2
w=3.86 ft. is the width of the walkway