Question

Draw a circle of radius 7cm. From a point 12 cm away from its centre, construct the pair of tangents to the circle and measure their lengths.

Answer 1

Here is your answer in the image

Answer 2

Answer:

The length of the tangent to the circle drawn from a point outside the circle could be calculated with the help of the Pythagorean Theorem.

As the tangent are perpendicular to the circle.

Hence, from the figure we have to find the length of side .AB and AC.

The hypotenuse of the right triangle is the line segment joining the outside point and the center of the circle.

Using Pythagorean theorem in ΔOBA we have:

OA²=AB²+OB²

12²=7²+AB²

AB²=12²-7²

i.eAB²=144 - 49

AB²=95

AB =√95

lengths of tangent are √95cm