Basic Geometry : Quadrilaterals
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Example Questions
Example Question #33 : 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 #141 : Quadrilaterals
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.
Example Question #1 : How To Find The Area Of A Rectangle
A rectangle has a perimeter of 
Given a rectangle, the general equation for the perimeter is 
Let 
So the equation to solve becomes 
Thus the area is
Example Question #1 : How To Find The Area Of A Rectangle
Which of the following information would not be sufficient to find the area of a rectangle?
The lengths of one side and a diagonal.
All of the other choices list information that would be sufficient.
The lengths of one pair of opposite sides.
The perimeter and the length of one side.
The lengths of one pair of adjacent sides.
The lengths of one pair of opposite sides.
The area of a rectangle can be calculated by multiplying the lengths of two adjacent sides. All of the choices given lists sufficient information, with one exception. We examine each of the choices.
The lengths of one pair of adjacent sides: This choice is false, as is directly stated above.
The perimeter and the length of one side: Using the perimeter formula, you can find the length of an adjacent side, making this choice false.
The lengths of one side and a diagonal: using the Pythagorean Theorem, you can find the length of an adjacent side, making this choice false.
The lengths of one pair of opposite sides: this gives you no way of knowing the lengths of the adjacent sides. This is the correct choice.
Example Question #1 : How To Find The Area Of A Rectangle
Find the area of the polygon.
Drawing a vertical line at the end of the side of length 
The sum of the areas of the two shapes is the area of the polygon. Multiply the length of the rectangle by its width to find the area of the rectangle, and use the formula 
Example Question #1 : How To Find The Area Of A Rectangle
One side of a rectangle is 7 inches and another is 9 inches. What is the area of the rectangle in inches?
To find the area of a rectangle, multiply its width by its height. If we know two sides of the rectangle that are different lengths, then we have both the height and the width.
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