How to find the length of the diagonal of a rectangle - ACT Math
Card 0 of 54
A rectangle has a height of 
 and a base of 
. What is the length of its diagonal rounded to the nearest tenth?
A rectangle has a height of  and a base of 
. What is the length of its diagonal rounded to the nearest tenth?
1. Use Pythagorean Theorem with 
 and 
.


2. Solve for 
, the length of the diagonal:




This rounds down to 
 because the hundredth's place (
) is less than 
.
1. Use Pythagorean Theorem with  and 
.
2. Solve for , the length of the diagonal:
This rounds down to  because the hundredth's place (
) is less than 
.
Compare your answer with the correct one above
The sides of rectangle ABCD are 4 in and 13 in.
How long is the diagonal of rectangle ABCD?
The sides of rectangle ABCD are 4 in and 13 in.
How long is the diagonal of rectangle ABCD?
A diagonal of a rectangle cuts the rectangle into 2 right triangles with sides equal to the sides of the rectangle and with a hypotenuse that is the diagonal. All you need to do is use the pythagorean theorem:
 where a and b are the sides of the rectangle and c is the length of the diagonal.

A diagonal of a rectangle cuts the rectangle into 2 right triangles with sides equal to the sides of the rectangle and with a hypotenuse that is the diagonal. All you need to do is use the pythagorean theorem:
 where a and b are the sides of the rectangle and c is the length of the diagonal.
Compare your answer with the correct one above
Mark bought a TV at the store that was listed as 36in x 24in. He needs to figure out the diagonal to make sure the television is large enough but he left his measuring tape at his mother's house. What is the diagonal length of this television's screen in terms of inches?
Mark bought a TV at the store that was listed as 36in x 24in. He needs to figure out the diagonal to make sure the television is large enough but he left his measuring tape at his mother's house. What is the diagonal length of this television's screen in terms of inches?
Finding the diagonal of a rectangle is essentially a problem with triangles. If we set up a right triangle with legs 24 in. and 36 in., and set 
 to be the diagonal (the hypotenuse), we can use the Pythagorean Theorem to solve for 
:


This comes out to be about 43.3 in.
Finding the diagonal of a rectangle is essentially a problem with triangles. If we set up a right triangle with legs 24 in. and 36 in., and set  to be the diagonal (the hypotenuse), we can use the Pythagorean Theorem to solve for 
:
This comes out to be about 43.3 in.
Compare your answer with the correct one above
A power company needs to run a piece of wire across a rectangular plot of land and must do so diagonally. The land is 
 
 by 
 
 in measurement. If it costs 
 for each mile of wire deployed, how much is the expected cost of this project? Round to the nearest cent.
A power company needs to run a piece of wire across a rectangular plot of land and must do so diagonally. The land is  
 by 
 
 in measurement. If it costs 
 for each mile of wire deployed, how much is the expected cost of this project? Round to the nearest cent.
Notice that this problem could be represented as follows:

This means that you can find the distance of the wire merely by using the Pythagorean theorem:

Solving for 
, you get:


Thus, 
Using your calculator, multiply this by 
. This gives you approximately 
 dollars in expenses.
Notice that this problem could be represented as follows:

This means that you can find the distance of the wire merely by using the Pythagorean theorem:
Solving for , you get:
Thus, 
Using your calculator, multiply this by . This gives you approximately 
 dollars in expenses.
Compare your answer with the correct one above
What is the diagonal of a rectangle with sides of length 
 and 
? Round to the nearest hundredth.
What is the diagonal of a rectangle with sides of length  and 
? Round to the nearest hundredth.
You could draw this rectangle as follows:

Solving for the diagonal merely requires using the Pythagorean theorem. Thus, you know:
 or

, meaning that 
This is approximately 
 Thus, the answer is 
.
You could draw this rectangle as follows:

Solving for the diagonal merely requires using the Pythagorean theorem. Thus, you know:
 or
, meaning that 
This is approximately  Thus, the answer is 
.
Compare your answer with the correct one above
What is the area of a rectangle with a diagonal of 
 
 and one side that is 
 
?
What is the area of a rectangle with a diagonal of  
 and one side that is 
 
?
Based on the description offered in the question, you know that your rectangle must look something like this:

Using the Pythagorean theorem, you can solve for the unknown side 
:



Thus, 
 is 
. This means that the area is 
 or 
 
.
Based on the description offered in the question, you know that your rectangle must look something like this:

Using the Pythagorean theorem, you can solve for the unknown side :
Thus,  is 
. This means that the area is 
 or 
 
.
Compare your answer with the correct one above
A rectangle has a height of 
 and a base of 
. What is the length of its diagonal rounded to the nearest tenth?
A rectangle has a height of  and a base of 
. What is the length of its diagonal rounded to the nearest tenth?
1. Use Pythagorean Theorem with 
 and 
.


2. Solve for 
, the length of the diagonal:




This rounds down to 
 because the hundredth's place (
) is less than 
.
1. Use Pythagorean Theorem with  and 
.
2. Solve for , the length of the diagonal:
This rounds down to  because the hundredth's place (
) is less than 
.
Compare your answer with the correct one above
The sides of rectangle ABCD are 4 in and 13 in.
How long is the diagonal of rectangle ABCD?
The sides of rectangle ABCD are 4 in and 13 in.
How long is the diagonal of rectangle ABCD?
A diagonal of a rectangle cuts the rectangle into 2 right triangles with sides equal to the sides of the rectangle and with a hypotenuse that is the diagonal. All you need to do is use the pythagorean theorem:
 where a and b are the sides of the rectangle and c is the length of the diagonal.

A diagonal of a rectangle cuts the rectangle into 2 right triangles with sides equal to the sides of the rectangle and with a hypotenuse that is the diagonal. All you need to do is use the pythagorean theorem:
 where a and b are the sides of the rectangle and c is the length of the diagonal.
Compare your answer with the correct one above
Mark bought a TV at the store that was listed as 36in x 24in. He needs to figure out the diagonal to make sure the television is large enough but he left his measuring tape at his mother's house. What is the diagonal length of this television's screen in terms of inches?
Mark bought a TV at the store that was listed as 36in x 24in. He needs to figure out the diagonal to make sure the television is large enough but he left his measuring tape at his mother's house. What is the diagonal length of this television's screen in terms of inches?
Finding the diagonal of a rectangle is essentially a problem with triangles. If we set up a right triangle with legs 24 in. and 36 in., and set 
 to be the diagonal (the hypotenuse), we can use the Pythagorean Theorem to solve for 
:


This comes out to be about 43.3 in.
Finding the diagonal of a rectangle is essentially a problem with triangles. If we set up a right triangle with legs 24 in. and 36 in., and set  to be the diagonal (the hypotenuse), we can use the Pythagorean Theorem to solve for 
:
This comes out to be about 43.3 in.
Compare your answer with the correct one above
A power company needs to run a piece of wire across a rectangular plot of land and must do so diagonally. The land is 
 
 by 
 
 in measurement. If it costs 
 for each mile of wire deployed, how much is the expected cost of this project? Round to the nearest cent.
A power company needs to run a piece of wire across a rectangular plot of land and must do so diagonally. The land is  
 by 
 
 in measurement. If it costs 
 for each mile of wire deployed, how much is the expected cost of this project? Round to the nearest cent.
Notice that this problem could be represented as follows:

This means that you can find the distance of the wire merely by using the Pythagorean theorem:

Solving for 
, you get:


Thus, 
Using your calculator, multiply this by 
. This gives you approximately 
 dollars in expenses.
Notice that this problem could be represented as follows:

This means that you can find the distance of the wire merely by using the Pythagorean theorem:
Solving for , you get:
Thus, 
Using your calculator, multiply this by . This gives you approximately 
 dollars in expenses.
Compare your answer with the correct one above
What is the diagonal of a rectangle with sides of length 
 and 
? Round to the nearest hundredth.
What is the diagonal of a rectangle with sides of length  and 
? Round to the nearest hundredth.
You could draw this rectangle as follows:

Solving for the diagonal merely requires using the Pythagorean theorem. Thus, you know:
 or

, meaning that 
This is approximately 
 Thus, the answer is 
.
You could draw this rectangle as follows:

Solving for the diagonal merely requires using the Pythagorean theorem. Thus, you know:
 or
, meaning that 
This is approximately  Thus, the answer is 
.
Compare your answer with the correct one above
What is the area of a rectangle with a diagonal of 
 
 and one side that is 
 
?
What is the area of a rectangle with a diagonal of  
 and one side that is 
 
?
Based on the description offered in the question, you know that your rectangle must look something like this:

Using the Pythagorean theorem, you can solve for the unknown side 
:



Thus, 
 is 
. This means that the area is 
 or 
 
.
Based on the description offered in the question, you know that your rectangle must look something like this:

Using the Pythagorean theorem, you can solve for the unknown side :
Thus,  is 
. This means that the area is 
 or 
 
.
Compare your answer with the correct one above
A rectangle has a height of 
 and a base of 
. What is the length of its diagonal rounded to the nearest tenth?
A rectangle has a height of  and a base of 
. What is the length of its diagonal rounded to the nearest tenth?
1. Use Pythagorean Theorem with 
 and 
.


2. Solve for 
, the length of the diagonal:




This rounds down to 
 because the hundredth's place (
) is less than 
.
1. Use Pythagorean Theorem with  and 
.
2. Solve for , the length of the diagonal:
This rounds down to  because the hundredth's place (
) is less than 
.
Compare your answer with the correct one above
The sides of rectangle ABCD are 4 in and 13 in.
How long is the diagonal of rectangle ABCD?
The sides of rectangle ABCD are 4 in and 13 in.
How long is the diagonal of rectangle ABCD?
A diagonal of a rectangle cuts the rectangle into 2 right triangles with sides equal to the sides of the rectangle and with a hypotenuse that is the diagonal. All you need to do is use the pythagorean theorem:
 where a and b are the sides of the rectangle and c is the length of the diagonal.

A diagonal of a rectangle cuts the rectangle into 2 right triangles with sides equal to the sides of the rectangle and with a hypotenuse that is the diagonal. All you need to do is use the pythagorean theorem:
 where a and b are the sides of the rectangle and c is the length of the diagonal.
Compare your answer with the correct one above
Mark bought a TV at the store that was listed as 36in x 24in. He needs to figure out the diagonal to make sure the television is large enough but he left his measuring tape at his mother's house. What is the diagonal length of this television's screen in terms of inches?
Mark bought a TV at the store that was listed as 36in x 24in. He needs to figure out the diagonal to make sure the television is large enough but he left his measuring tape at his mother's house. What is the diagonal length of this television's screen in terms of inches?
Finding the diagonal of a rectangle is essentially a problem with triangles. If we set up a right triangle with legs 24 in. and 36 in., and set 
 to be the diagonal (the hypotenuse), we can use the Pythagorean Theorem to solve for 
:


This comes out to be about 43.3 in.
Finding the diagonal of a rectangle is essentially a problem with triangles. If we set up a right triangle with legs 24 in. and 36 in., and set  to be the diagonal (the hypotenuse), we can use the Pythagorean Theorem to solve for 
:
This comes out to be about 43.3 in.
Compare your answer with the correct one above
A power company needs to run a piece of wire across a rectangular plot of land and must do so diagonally. The land is 
 
 by 
 
 in measurement. If it costs 
 for each mile of wire deployed, how much is the expected cost of this project? Round to the nearest cent.
A power company needs to run a piece of wire across a rectangular plot of land and must do so diagonally. The land is  
 by 
 
 in measurement. If it costs 
 for each mile of wire deployed, how much is the expected cost of this project? Round to the nearest cent.
Notice that this problem could be represented as follows:

This means that you can find the distance of the wire merely by using the Pythagorean theorem:

Solving for 
, you get:


Thus, 
Using your calculator, multiply this by 
. This gives you approximately 
 dollars in expenses.
Notice that this problem could be represented as follows:

This means that you can find the distance of the wire merely by using the Pythagorean theorem:
Solving for , you get:
Thus, 
Using your calculator, multiply this by . This gives you approximately 
 dollars in expenses.
Compare your answer with the correct one above
What is the diagonal of a rectangle with sides of length 
 and 
? Round to the nearest hundredth.
What is the diagonal of a rectangle with sides of length  and 
? Round to the nearest hundredth.
You could draw this rectangle as follows:

Solving for the diagonal merely requires using the Pythagorean theorem. Thus, you know:
 or

, meaning that 
This is approximately 
 Thus, the answer is 
.
You could draw this rectangle as follows:

Solving for the diagonal merely requires using the Pythagorean theorem. Thus, you know:
 or
, meaning that 
This is approximately  Thus, the answer is 
.
Compare your answer with the correct one above
What is the area of a rectangle with a diagonal of 
 
 and one side that is 
 
?
What is the area of a rectangle with a diagonal of  
 and one side that is 
 
?
Based on the description offered in the question, you know that your rectangle must look something like this:

Using the Pythagorean theorem, you can solve for the unknown side 
:



Thus, 
 is 
. This means that the area is 
 or 
 
.
Based on the description offered in the question, you know that your rectangle must look something like this:

Using the Pythagorean theorem, you can solve for the unknown side :
Thus,  is 
. This means that the area is 
 or 
 
.
Compare your answer with the correct one above
A rectangle has a height of 
 and a base of 
. What is the length of its diagonal rounded to the nearest tenth?
A rectangle has a height of  and a base of 
. What is the length of its diagonal rounded to the nearest tenth?
1. Use Pythagorean Theorem with 
 and 
.


2. Solve for 
, the length of the diagonal:




This rounds down to 
 because the hundredth's place (
) is less than 
.
1. Use Pythagorean Theorem with  and 
.
2. Solve for , the length of the diagonal:
This rounds down to  because the hundredth's place (
) is less than 
.
Compare your answer with the correct one above
The sides of rectangle ABCD are 4 in and 13 in.
How long is the diagonal of rectangle ABCD?
The sides of rectangle ABCD are 4 in and 13 in.
How long is the diagonal of rectangle ABCD?
A diagonal of a rectangle cuts the rectangle into 2 right triangles with sides equal to the sides of the rectangle and with a hypotenuse that is the diagonal. All you need to do is use the pythagorean theorem:
 where a and b are the sides of the rectangle and c is the length of the diagonal.

A diagonal of a rectangle cuts the rectangle into 2 right triangles with sides equal to the sides of the rectangle and with a hypotenuse that is the diagonal. All you need to do is use the pythagorean theorem:
 where a and b are the sides of the rectangle and c is the length of the diagonal.
Compare your answer with the correct one above