Question

Draw a triangle with two sides equal to 5 cm and 6 cm and the angle between them is 45${}^{\circ }$. Then the circumradius of this triangle measures

• A. 1.9 cm
• B. 2.2 cm
• C. 2.8 cm
• D. 3.4 cm

Answer 1

The correct option is C

2.8 cm

Draw a triangle ABC with the given specifications, AB=5 cm, AC = 6 cm and $\angle$BAC = 45${}^{\circ }$.

Draw perpendicular bisectors of sides AB and AC, they meet at O. Join OB.

So, O is the centre and OB is the radius of the circumcircle of $△$ABC.

From the above constructions, we see that the circumradius of $△$ABC is 2.8 cm.