Recalling the Formulas for Area and Perimeter

Oct 13, 2025 by wbrum.org 41 views

In this problem, we are given the area and perimeter of a tabletop and asked to find its dimensions. The area of the tabletop is 12 square feet, and the perimeter is 16 feet. We need to use this information to determine the length and width of the tabletop.

Recalling the Formulas for Area and Perimeter

Before we proceed, let's recall the formulas for the area and perimeter of a rectangle, which is the shape of the tabletop.

The area of a rectangle is given by the formula: A = length × width
The perimeter of a rectangle is given by the formula: P = 2(length + width)

Using the Given Information to Set Up Equations

We are given that the area of the tabletop is 12 square feet, so we can set up an equation using the area formula:

12 = length × width

We are also given that the perimeter of the tabletop is 16 feet, so we can set up another equation using the perimeter formula:

16 = 2(length + width)

Simplifying the Perimeter Equation

To simplify the perimeter equation, we can divide both sides by 2:

8 = length + width

Solving the System of Equations

Now we have two equations:

12 = length × width
8 = length + width

We can solve this system of equations by substitution or elimination. Let's use substitution.

Rearranging the Second Equation

Rearrange the second equation to isolate one variable:

length = 8 - width

Substituting into the First Equation

Substitute the expression for length into the first equation:

12 = (8 - width) × width

Expanding and Simplifying

Expand and simplify the equation:

12 = 8w - w^2

Rearranging into Standard Quadratic Form

Rearrange the equation into standard quadratic form:

w^2 - 8w + 12 = 0

Factoring the Quadratic Equation

Factor the quadratic equation:

(w - 6)(w - 2) = 0

Solving for Width

Solve for width:

w - 6 = 0 or w - 2 = 0

w = 6 or w = 2

Finding the Length

Now that we have the width, we can find the length using the equation:

length = 8 - width

length = 8 - 6 = 2
length = 8 - 2 = 6

Checking the Solutions

We have two possible solutions:

width = 6 and length = 2
width = 2 and length = 6

Both solutions satisfy the original equations, so we can conclude that the dimensions of the tabletop are either 2 ft by 6 ft or 6 ft by 2 ft.

Conclusion

In this problem, we used the given area and perimeter of a tabletop to find its dimensions. We set up equations using the area and perimeter formulas, simplified the equations, and solved the system of equations to find the width and length of the tabletop. The dimensions of the tabletop are either 2 ft by 6 ft or 6 ft by 2 ft.

Answer

The correct answer is:

A. 2 ft by 6 ft
B. 2 ft by 8 ft is incorrect
C. 4 ft by 3 ft is incorrect
D. 4 ft by 4 ft is incorrect
A Tabletop with Given Area and Perimeter: Q&A =============================================

Q: What is the formula for the area of a rectangle?

A: The formula for the area of a rectangle is A = length × width.

Q: What is the formula for the perimeter of a rectangle?

A: The formula for the perimeter of a rectangle is P = 2(length + width).

Q: How do we use the given area and perimeter to find the dimensions of the tabletop?

A: We set up equations using the area and perimeter formulas, simplify the equations, and solve the system of equations to find the width and length of the tabletop.

Q: What are the two possible solutions for the dimensions of the tabletop?

A: The two possible solutions for the dimensions of the tabletop are:

width = 6 and length = 2
width = 2 and length = 6

Q: Why are both solutions correct?

A: Both solutions satisfy the original equations, so we can conclude that the dimensions of the tabletop are either 2 ft by 6 ft or 6 ft by 2 ft.

Q: What is the correct answer among the given options?

A: The correct answer is:

A. 2 ft by 6 ft

Q: Why is option B incorrect?

A: Option B is incorrect because the dimensions of the tabletop are not 2 ft by 8 ft.

Q: Why is option C incorrect?

A: Option C is incorrect because the dimensions of the tabletop are not 4 ft by 3 ft.

Q: Why is option D incorrect?

A: Option D is incorrect because the dimensions of the tabletop are not 4 ft by 4 ft.

Q: What is the main concept used to solve this problem?

A: The main concept used to solve this problem is the use of the area and perimeter formulas to find the dimensions of a rectangle.

Q: What is the importance of solving this problem?

A: Solving this problem helps to understand how to use the area and perimeter formulas to find the dimensions of a rectangle, which is a fundamental concept in geometry and mathematics.

Q: How can this problem be applied in real-life situations?

A: This problem can be applied in real-life situations such as designing furniture, building construction, and architecture, where the dimensions of a rectangle need to be determined.

Conclusion

In this Q&A article, we have discussed the problem of finding the dimensions of a tabletop with given area and perimeter. We have used the area and perimeter formulas to set up equations, simplify the equations, and solve the system of equations to find the width and length of the tabletop. The correct answer is 2 ft by 6 ft.