draw a circle of radius 6 cm from a point in centimetre away from the centre construct the pair of tangents and the circle and measure the length verified by using Pythagoras theorem
Answers
HELLO DEAR
[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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