Calculate Rectangle Diagonal Length: Finding BD When AB=4 and AD=3

Question

Given the rectangle ABCD

It is known that:

AB=4

AD=3

What is the length of the diagonal BD?

00:00 Find diagonal BD

00:04 Side values according to the given data

00:13 We'll use the Pythagorean theorem in triangle ABD

00:22 We'll substitute appropriate values and solve for BD

00:31 And this is the solution to the question

We will use the Pythagorean theorem in order to find BD:

$BD^2=AD^2+AB^2$

Let's input the known data:

$BD^2=3^2+4^2$

$BD^2=9+16$

$BD^2=25$

We'll take the square root:

$BD=\sqrt{25}=5$

$5$