If the width of the walkway is x and the dimensions of the garden are 9m by 14m, the area of the garden is 126m² and the area of the walkway is (2x+9)(2x+14)=4x²+46x+126-126=4x²+46. This has to use 140m² of material so 4x²+46x=140 or 2x²+23x-70=0=(2x-5)(x+14). So 2x=5 and x=2.5m. The equation is highlighted in bold, and its solution is 2.5m, meaning that the walkway has a width of 2.5m all around the garden. (The dimensions of the walkway around the garden are 14m by 19m.)