A circle C1 has a centre at (3,0) and a radius 8. A second circle C2 has a centre (x,0) and radius 6. Given the radii of the 2 circles meet at right angles. Find x

Gven the radii of the circles meet at right angles then a right angled triangle can be constructed were the hypotenuse is the distance between the centres. Using the Pythagorean triplet, the hypotenuse is 10. Therefore x is 13