The surface of an air hockey table has an area of 40 square feet and a perimeter of 28 feet. What are the dimensions of the air hockey table?___ feet by ___ feet
Q. The surface of an air hockey table has an area of 40 square feet and a perimeter of 28 feet. What are the dimensions of the air hockey table?___ feet by ___ feet
Define Area Formula: Let l and w be the length and width of the air hockey table, respectively. The area of a rectangle is given by A=l×w.
Substitute Area Value: Given area A=40 square feet. Substitute into the area formula: 40=l×w.
Define Perimeter Formula: The perimeter of a rectangle is given by P=2l+2w. Given perimeter P=28 feet. Substitute into the perimeter formula: 28=2l+2w.
Substitute Perimeter Value: Simplify the perimeter equation: 14=l+w.
Simplify Perimeter Equation: We now have two equations: 40=l×w and 14=l+w. Solve these equations simultaneously.
Solve Equations Simultaneously: Substitute w=14−l into the area equation: 40=l×(14−l).
Substitute Width into Area Equation: Expand and rearrange the equation: 40=14l−l2. Rearrange to form a quadratic equation: l2−14l+40=0.
Expand and Rearrange Equation: Solve the quadratic equation using the quadratic formula, l=2a−b±b2−4ac. Here, a=1, b=−14, and c=40.
Solve Quadratic Equation: Calculate the discriminant: (−14)2−4⋅1⋅40=196−160=36.
Calculate Discriminant: Calculate the roots: l=214±36. So, l=214±6.
Calculate Roots: This gives l=10 or l=4. If l=10, then w=14−10=4. If l=4, then w=14−4=10.
More problems from Area and perimeter: word problems