Question

3. a) Draw a line AB = 5cm and a point C on it. Draw a line CD
perpendicular to AB.​

Answer 1

steps for construction

·         draw AB=5cm

·         with A as centre cut an arc of 3cm on AB and mark it C

·         with A as centre and radius 2.5cm, draw an arc and mark it O

·         with O as centre and radius 2.5cm, draw a circle so that points A and C lie on the circle formed

·         join OB

·         draw perpendicular bisector of OB to obtain mid point of OB, M

·         with M as the centre and radius equal to OM, draw a circle to cut the previous circle at point P and Q

.       join PB and QB, PB and QB are required tangents to the given circle from exterior point B

QB=PB=3cm

The length of the tangents is 3cm