The width of the walkway around the community garden is 2 ft.
The given parameters;
Let the width of the walkway = x
Length of the garden and the walkway = 15 + (x + x) = 15 + 2x
Width of the garden and the walkway = 12 + (x + x) = 12 + 2x
Area of the garden and the walkway = (15 + 2x)(12 + 2x)
304 = (15 + 2x)(12 + 2x)
304 = 180 + 30x + 24x + 4x²
304 = 180 + 54x + 4x²
divide through by 4;
76 = 45 + 13.5x + x²
x² + 13.5x - 31 = 0
Solve the quadratic equation using formula method;
a = 1, b = 13.5, c = -31
[tex]x = \frac{-b \ + /- \ \ \sqrt{b^2 -4ac} }{2a} \\\\x = \frac{-13.5 \ + /- \ \ \sqrt{(13.5)^2 -4(1\times -31)} }{2(1)} \\\\x = 2 \ \ \ or \ \ -15.5[/tex]
The width cannot be negative, so we choose 2 ft as the width of the walkway.
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