Question

A point P is at a distance of 29 cm from the centre of a circle of radius 20 centimetre find the length of the tangent drawn from P to the circle

Answer 1

OP²=QP²+OQ²
(29)²=QP²+(20)²
841-400=QP²
441=QP²
QP=21
21 is the answer

Answer 2

Answer:

$\red { Length \: of \:the \: tangent} \green {= 21\:cm }$

Step-by-step explanation:

$Distance \: from \: center \: of \: the\: Circle \\to \: a \: point \:P \blue {(d )} = 29\:cm$

$Radius \: of \: circle (r) = 20 \:cm$

$\boxed { \pink { Length \: of \:the \: tangent = \sqrt{ d^{2} - r^{2}}}}$

$= \sqrt{ 29^{2} - 20^{2}}\\= \sqrt{ (29+20)(29-20)}\\= \sqrt{49 \times 9}\\= 7\times 3\\= 21 \:cm$

Therefore.,

$\red { Length \: of \:the \: tangent} \green {= 21\:cm }$

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