Geometry - How to find the area of a rectangle

If the perimeter of a rectangle is , and the width of the rectangle is , what is the area of a rectangle?

Explanation

Recall how to find the perimeter of a rectangle:

$\text{Perimeter}=2(\text{length}+\text{width})$

Since we are given the width and the perimeter, we can solve for the length.

$\text{length}+\text{width}=\frac{\text{Perimeter}}{2}$

$\text{length}=\frac{\text{Perimeter}}{2}-\text{width}$

Substitute in the given values for the width and perimeter to find the length.

$\text{length}=\frac{36}{2}-17$

Simplify.

$\text{length}=18-17$

Solve.

$\text{length}=1$

Now, recall how to find the area of a rectangle.

$\text{Area}=\text{length}\times\text{width}$

Substitute in the values of the length and width to find the area.

$\text{Area}=17 \times 1$

Solve.

$\text{Area}=17$

If a rectangle has a width of and a length that is double the width, what would be the area of the rectangle? Round to the nearest tenth.

Explanation

To calculate the area of a triangle, we want to multiply the length by the width. Since the length is twice that of the width, which is , we can determine length as such:

$2.3;cm\cdot2=4.6;cm$

Now that we know the values for length and width, we can calculate the area of the triangle:

$Area=2.3;cm\cdot4.6;cm=10.6;cm^2$

If the perimeter of a rectangle is , and the length of the rectangle is , what is the area of the rectangle?

Explanation

First, use the information given about the perimeter to find the width of the rectangle.

Recall how to find the perimeter of a rectangle:

$\text{Perimeter}=2(\text{length}+\text{width})$

From this equation, we can solve for the width.

$\text{length}+\text{width}=\frac{\text{Perimeter}}{2}$

$\text{width}=\frac{\text{Perimeter}}{2}-\text{length}$

Substitute in the information from the question to find the width of the rectangle.

$\text{Width}=\frac{48}{2}-10$

Simplify.

$\text{Width}=14$

Now, recall how to find the area of a rectangle:

$\text{Area}=\text{length}\times\text{width}$

Substitute in the information about the length and width to find the area for the rectangle in question.

$\text{Area}=10 \times 14$

Solve.

$\text{Area}=140$

Rec 7

Find the area of the rectangle.

Explanation

To find the area of any rectangle, multiply the base and height.

Use this formula:

In this case, the base is 42 and the height is 89.

When we multiply 42 by 89, the answer is 3738, so that is the area of the rectangle.

If Betty's barn with a width of and a length that is short of four times the width, what would be the area of the floor space of the barn?

Explanation

To find the area of the barn, we must first find the length. We can do this by using the given information to draft an algebraic equation:

$\Length'=4(width')-32'\L=4\cdot35'-32'\L=140'-32'=108'$

Now that we know both the length and width, we can determine the area of the barn:

$Area=35;ft\cdot108;ft=3,780;ft^2$

If the perimeter of a rectangle is , and the width of the rectangle is , what is the area of the rectangle?

Explanation

Recall how to find the perimeter of a rectangle:

$\text{Perimeter}=2(\text{length}+\text{width})$

Since we are given the width and the perimeter, we can solve for the length.

$\text{length}+\text{width}=\frac{\text{Perimeter}}{2}$

$\text{length}=\frac{\text{Perimeter}}{2}-\text{width}$

Substitute in the given values for the width and perimeter to find the length.

$\text{length}=\frac{36}{2}-12=6$

Simplify.

$\text{length}=\frac{36}{2}-12=6$

Solve.

$\text{length}=\frac{36}{2}-12=6$

Now, recall how to find the area of a rectangle.

$\text{Area}=\text{length}\times\text{width}$

Substitute in the values of the length and width to find the area.

$\text{Area}=12 \times 6$

Solve.

$\text{Area}= 72$

What is the area of a rectangle that has a length of and a width of ?

Explanation

Recall how to find the area of a rectangle:

$\text{Area}=\text{length}\times\text{width}$

Now, plug in the given length and width to find the area.

When multiplying decimals together first move the decimal over so that the number is a whole integer.

$0.75\rightarrow 75$

Now we multiple the integers together.

$0.75\cdot 85\rightarrow 75\cdot 85=6375$

From here, we need to move the decimal place back. In this particular problem we moved the decimal over a total of two decimal places.

Therefore our answer becomes,

$6375\rightarrow 63.75$

$\text{Area}=85 \times 0.75= 63.75$

What is the area of a rectangle that has a length of and a width of ?

Explanation

Recall how to find the area of a rectangle:

$\text{Area}=\text{length}\times\text{width}$

Now, plug in the given length and width to find the area.

When multiplying decimals together first move the decimal over so that the number is a whole integer.

$12.5\rightarrow 125$

Now we multiple the integers together.

$12.5\cdot 10\rightarrow 125\cdot 10=1250$

From here, we need to move the decimal place back. In this particular problem we moved the decimal over one place.

Therefore our answer becomes,

$1250\rightarrow 125.0$

$\text{Area}=12.5 \times 10= 125$

What is the area of a rectangle that has a length of and a width of ?

Explanation

Recall how to find the area of a rectangle:

$\text{Area}=\text{length}\times\text{width}$

Now, plug in the given length and width to find the area.

$\text{Area}=12 \times 10= 120$

What is the area of a rectangle that has a length of and a width of ?

Explanation

Recall how to find the area of a rectangle:

$\text{Area}=\text{length}\times\text{width}$

Now, plug in the given length and width to find the area.

$\text{Area}=100 \times 4= 400$

How to find the area of a rectangle

Help Questions

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation