Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Geometry

Question:

The length of the tangent drawn to a circle of radius 12 cm from a point 18 cm away from the centre of the circle is:

Options:

$3\sqrt{5}$ cm

$6\sqrt{5}$ cm

$9\sqrt{5}$ cm

$2\sqrt{5}$ cm

Correct Answer:

$6\sqrt{5}$ cm

Explanation:

In triangle AOB,

By using pythagoras theorem,

h² = b² + p²

OA² = OB² + AB²

18² = 12² + AB²

AB² = 324 - 144

AB² = 180

AB = 6√5 cm