Question Detail
Question
When constructing a cross tangent to two unequal circles (Page 16) with radii R and r, what specific radius is used to draw a circle from the center of the larger circle (O) to cut the semi-circle?
Correct Answer
Option D is the correct answer.
Detailed Explanation
Page 16, step 4 for 'To Construct a Cross Tangent to Two UNEqual Circles' instructs: 'Draw a circle centre O with radius (R+r) to cut semi-circle at B.'
Hint
For a *common cross* tangent to unequal circles, the sum of the radii is often used.