Question
Using ruler and compasses only, construct and equilateral triangle with side 4.5 cm. Draw a circumcircle of this triangle and measure its radius.
✓
Answer
Steps of construction:
(i) Draw line AB= 4.5 cm
(ii) At B 1 draw an arc making an angle of 60" • with AB and Ieng th BC = 4. 5 cm.
(iii) On the arc cut AC = 4.5 cm.
(iv) Join AC.
(v) Draw perpendicular bisectors of AB and BC, which meet at O.
(vi) With O as centre and radius equal to the distance between O and the vertex of the triangle 1 draw a cricle to pass through alI the
three vertices of the triangle.
(vii) The drawn circle is the required circle with radius= 2.6 cm
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