Basic Geometry : How to find the length of the diagonal of a rectangle
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Example Question #31 : How To Find The Length Of The Diagonal Of A Rectangle
If a rectangle is inscribed in a circle with a circumference of 
You should notice that the diagonal of the rectangle is the same as the diameter of the circle.
Now, recall how to find the circumference of a circle.
Since we are given the circumference and need the diameter, rerwite the equation to solve for the diameter.
Plug in the given circumference to find the diameter.
Now, recall the relationship between the diameter of the circle and the diagonal of the rectangle:
Example Question #32 : How To Find The Length Of The Diagonal Of A Rectangle
Find the length of the diagonal of a rectangle with side lengths 6 and 7.
To find the diagonal of a rectangle recall that the diagonal will create a triangle where the width and length are legs of the triangle and the diagonal is the hypotenuse.
To solve, simple use the Pythagorean Theorem and solve for the hypotenuse, which will be the diagonal of the rectangle.
Thus,
Example Question #33 : How To Find The Length Of The Diagonal Of A Rectangle
A rectangle has a width of 
First we must find the length of the rectangle before we can solve for the diagonal. With a length 
Now that we know the values for length and width, we can use the Pythagorean Theorem to solve for the diagonal:
Example Question #34 : How To Find The Length Of The Diagonal Of A Rectangle
Sarah's new tablet has a screen width of 
If the width is 
Example Question #35 : How To Find The Length Of The Diagonal Of A Rectangle
Find the length of the diagonal of a rectangle with length 7 and width 2.
To solve, simply use the Pythagorean Theorem. Thus,
Example Question #35 : How To Find The Length Of The Diagonal Of A Rectangle
A rectangle has sides of length 
The diagonal of a rectangle forms the hypotenuse of a right triangle with one long and one short side of the rectangle. Therefore, to find the diagonal, we use the Pythagorean Theorem using the two side lengths and solving for the hypotenuse:
Then, all we have to do is simplify the radical, as follows:
Therefore, 
Example Question #34 : How To Find The Length Of The Diagonal Of A Rectangle
A rectangular pen has side lengths of 15 meters and 10 meters. Suppose a fence must be built from one corner diagonally across to the opposite corner. Approximately how many meters of fence will be needed?
None of these.
Rectangles have long and short sides which are opposite each other. The diagonal that runs from the opposite corner across the rectangle forms a right angle.
Use Pythagorean Theorem to find the length of the diagonal.
Example Question #551 : Plane Geometry
If a laptop screen has a length of 
To find the diagonal length, we must first find the width of the rectangular screen. With the given information, we can use the formula for area of a rectangle to find the missing value:
Now that we know the length and width, we can use the Pythagorean Theorem to solve for the diagonal length:
Example Question #37 : How To Find The Length Of The Diagonal Of A Rectangle
The length of a rectangle is 4cm and the width is 3cm. What is the length of the diagonal?
The diagonal can be found using Pythagorean Theorem.
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