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draw a circle of 6 cm from a point 10 centimetre away from its Centre construct the pair of a tangent of the circle and measure their length? |
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Answer» <P>Answer: Step-by-step explanation: figure is in the attachment] A pair of tangents to the given circle can be constructed as follows. Step 1 Taking any point O of the given plane as centre, DRAW a circle of 6 cm radius. Locate a point P, 10 cm away from O. Join OP. Step 2 Bisect OP. Let M be the mid-point of PO. Step 3 Taking M as centre and MO as radius, draw a circle. Step 4 Let this circle intersect the previous circle at point Q and R. Step 5 Join PQ and PR. PQ and PR are the REQUIRED tangents. The LENGTHS of tangents PQ and PR are 8 cm each. Justification The construction can be justified by proving that PQ and PR are the tangents to the circle (whose centre is O and radius is 6 cm). For this, join OQ and OR. ∠PQO is an angle in the semi-circle. We know that angle in a semi-circle is a right angle. ∴ ∠PQO = 90° ⇒ OQ ⊥ PQ Since OQ is the radius of the circle, PQ has to be a tangent of the circle. Similarly, PR is a tangent of the circle. now, justification by Pythagoras theorem; IN ∆ OPQ, OP² = PQ² + OQ² (10)² = PQ² + (6)² 100 - 36 = PQ² PQ = √64 PQ = 8 I HOPE ITS HELP YOU DEAR, THANKS |
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