Rectangle Area Problem: Finding BC When AB = 5cm and Area = 30cm²

Question

Below is the rectangle ABCD, which has an area of 30 cm².

Side AB is equal to 5 cm.
What is the length of side BC?

00:10 Let's find the length of side B C in this rectangle.

00:14 To solve this, we'll use the area formula for a rectangle, which is length times width.

00:20 We multiply side A B by side B C to get the area.

00:24 To make this easier, let's call the unknown side B C 'x'.

00:29 Now, we can put our known values into the formula and solve for x, step by step.

00:35 And there we have it! That's how we find the length of side B C.

First, we will multiply side AB by side BC.

We know that side BC equals 5, therefore:

$AB\times BC=AB\times5$

We will label side AB as $x$ .

Therefore:

$5x=30$

Next, we will divide both sides by 5 to obtain the following:

$x=6$

Therefore:
$BC=6$

6 cm