Question

How many arcs are drawn to construct a triangle PQR in which $QR=6cm,\angle Q={60}^{\circ }andPR-PQ=2cm$.

• A. 2
• B. 4
• C. 7
• D. 6

Answer 1

The correct option is C 7


Steps to construct the required triangle are as follows :
Step 1: Draw a line segment QR of 6cm. At point Q, draw an angle of ${60}^{\circ }$, say $\angle XQR={60}^{\circ }$[2 arcs].
Step 2: Cut a line segment QS = PR-PQ = 2cm [1 arc] from the line QX extended on the opposite side of line segment QR and join SR.
Step 3: Draw perpendicular bisector AB of line segment SR [4 arcs]. Let it intersect QX at point P.
Step 4: Join PR, then $\Delta PQR$ is the required triangle.

$\therefore$ 2 + 1 + 4 = 7 arcs are drawn in total to construct the given triangle.