posted by Aria .
A contact lens has a spherical shape and pretend it is being held on a finger ready to put into an eye. (All measures are in millimetres.) Suppose we take the semi-circular cross-section through the middle of the lens. Find the equation of the lens if the centrepoint of the cross-section is (0,3) and a speck of dirt on the lens at (3,3)Find the radius. Round off your answer to the nearest decimal place.
Then find the height of a point that is 2 mm from the centre. Round off your answer to the nearest decimal place.