A chord 6.6m long is 5.6m from the centre of the circle.find the radius of the circle.

1 answer

Make a sketch.
the line from the centre hits the chord at its midpoint and you have a right-angled triangle.

You can use Pythagoras.

r^2 = 3.3^2 + 5.6^2 = 42.25
r = √42.25 = 6.5