# Basic Geometry : How to find circumference

## Example Questions

### Example Question #61 : How To Find Circumference

The rectangle and the circle share the same center, . Find the circumference of the circle.

Explanation:

Notice that the diagonal of the rectangle is also the diameter of the circle.

Use the Pythagorean theorem to find the length of the diagonal.

Substitute in the values of the length and the width to find the length of the diagonal.

Simplify.

Reduce.

Now, recall the relationship between the diagonal and the diameter.

Recall how to find the circumference of a circle:

Substitute in the value of the diameter to find the circumference.

### Example Question #62 : How To Find Circumference

The rectangle and the circle share the same center, . Find the circumference of the circle.

Explanation:

Notice that the diagonal of the rectangle is also the diameter of the circle.

Use the Pythagorean theorem to find the length of the diagonal.

Substitute in the values of the length and the width to find the length of the diagonal.

Simplify.

Reduce.

Now, recall the relationship between the diagonal and the diameter.

Recall how to find the circumference of a circle:

Substitute in the value of the diameter to find the circumference.

### Example Question #63 : How To Find Circumference

Find the circumference of a circle given radius .

Explanation:

To solve, simply use the formula for circumference. Thus,

### Example Question #64 : How To Find Circumference

If a rectangle with a diagonal of  is inscribed in a circle, what is the circumference of the circle?

Explanation:

Notice that the diagonal of the rectangle is the same as the diameter of the circle.

Now, recall how to find the circumference of a circle.

Substitute in the given diameter to find the circumference.

### Example Question #65 : How To Find Circumference

If a rectangle with a diagonal of  is inscribed in a circle, what is the circumference of the circle?

Explanation:

Notice that the diagonal of the rectangle is the same as the diameter of the circle.

Now, recall how to find the circumference of a circle.

Substitute in the given diameter to find the circumference.

### Example Question #66 : How To Find Circumference

If a rectangle with a diagonal of  is inscribed in a circle, what is the circumference of the circle?

Explanation:

Notice that the diagonal of the rectangle is the same as the diameter of the circle.

Now, recall how to find the circumference of a circle.

Substitute in the given diameter to find the circumference.

### Example Question #67 : How To Find Circumference

If a rectangle with a diagonal of  is inscribed in a circle, what is the circumference of the circle?

Explanation:

Notice that the diagonal of the rectangle is the same as the diameter of the circle.

Now, recall how to find the circumference of a circle.

Substitute in the given diameter to find the circumference.

### Example Question #68 : How To Find Circumference

If a rectangle with a diagonal of  is inscribed in a circle, what is the circumference of the circle?

Explanation:

Notice that the diagonal of the rectangle is the same as the diameter of the circle.

Now, recall how to find the circumference of a circle.

Substitute in the given diameter to find the circumference.

### Example Question #69 : How To Find Circumference

If a rectangle with a diagonal of  is inscribed in a circle, what is the circumference of the circle?

Explanation:

Notice that the diagonal of the rectangle is the same as the diameter of the circle.

Now, recall how to find the circumference of a circle.

Substitute in the given diameter to find the circumference.

### Example Question #70 : How To Find Circumference

If a rectangle with a diagonal of  is inscribed in a circle, what is the circumference of the circle?