Calculate Circle Area: Finding the Area When Diameter = 13

Question

Look at the circle in the figure:

The diameter of the circle is 13.

What is its area?

00:00 Calculate the area of the circle

00:03 The diameter of the circle according to the given data

00:07 The diameter of the circle equals twice the radius

00:11 Let's calculate the radius

00:14 Use the formula to calculate the circle's area

00:17 Substitute the radius value and solve to find the area

00:20 And this is the solution to the problem

First, let's remember what the formula for the area of a circle is:

$S=\pi r^2$

The problem gives us the diameter, and we know that the radius is half of the diameter therefore:

$\frac{13}{2}=6.5$

We replace in the formula and solve:

$S=\pi\times6.5^2$

$S=42.25\pi$

42.25π