Olivia has a 20-meter-long fence that she plans to use to enclose a rectangular garden of width w. The fencing will be placed around all four sides of the garden so that its area is 18.75 square meters.Write an equation in terms of w that models the situation.
Q. Olivia has a 20-meter-long fence that she plans to use to enclose a rectangular garden of width w. The fencing will be placed around all four sides of the garden so that its area is 18.75 square meters.Write an equation in terms of w that models the situation.
Perimeter Equation: The perimeter of the rectangular garden is equal to the length of the fence, which is 20 meters. The perimeter P of a rectangle is given by P=2l+2w, where l is the length and w is the width.
Total Perimeter: Since we know the total perimeter is 20 meters, we can write the equation as 20=2l+2w.
Area Equation: We also know the area A of the rectangle is given by A=l×w, and the area is 18.75 square meters. So we have 18.75=l×w.
Expressing Length in Terms of Width: To write an equation in terms of w, we need to express l in terms of w using the area equation. From the area equation, we get l=w18.75.
Substitution into Perimeter Equation: Now we substitute l=w18.75 into the perimeter equation: 20=2(w18.75)+2w.
Simplify Equation: Simplify the equation: 20=w37.5+2w.
Eliminating Fraction: To make it look neater, we can multiply every term by w to get rid of the fraction: 20w=37.5+2w2.
Quadratic Equation: Rearrange the terms to get a quadratic equation in standard form: 2w2−20w+37.5=0.
More problems from Evaluate two-variable equations: word problems