- A12 cm
- B13 cm
- C5 cm
- D6.5 cm
Step-by-Step Solution
The centres are 9 + 4 = 13 cm apart, so the direct common tangent is cm. (In general it equals )
Answer: A) 12 cm
Two circles of radii 9 cm and 4 cm touch each other externally. Find the length of their direct common tangent.
Competition practiceGeometry
Master this topic in 30 minutes a day.
Don't just memorise the answer — build a daily practice habit.
Practice 5 Similar Questions Free →All Geometry practice questions
More Geometry practice
Circles of radii 5 cm and 3 cm have centres exactly 8 cm apart. How many common tangents…How many common tangents do two circles of radii 6 cm and 4 cm have if their centres are…From a point P, 12 cm from the centre of a circle of radius 6 cm, two tangents are…Tangents PA and PB are drawn to a circle of radius 5 cm from a point P that is 13 cm…Three circles touch one another externally. The distances between their centres are 7…