Find the radius of the circle if the center is at (1, 2) and the point (-3, 4) lies on the circle?

Solution:

Given the center is at (1, 2)

The point (-3, 4) lies on the circle

Radius can be calculated as the distance between the centre to any point on the circle.

Radius = √{(y\(_2\) - y\(_1\))² + (x\(_2\) - x\(_1\))²}

= √{(4 - 2)² + (-3 - 1)²}

= √{ 4 + 16}

= √20

Radius = √20 = 2√5

Find the radius of the circle if the center is at (1, 2) and the point (-3, 4) lies on the circle?

Summary:

The radius of the circle if the center is at (1, 2) and the point (-3, 4) lies on the circle is 2√5