1. Construct a triangle ABC when

     AB = 6.0 cm,BC = 8.0 cm and AC = 7.5 cm(ie,if three sides are given)

        1. Draw AB = 6 cm

        2. With A as centre and radius = 7.5 cm,draw an arc

        3. With B as centre and radius = 8 cm,draw one more arc,which cuts the former arc at C.

        4. Join AC and BC.ABC is the required triangle.

2. Construct a triangle PQR,when QR = 3.6 cm,RP = 3 cm and R = 45^o

      (ie,if lengths of two of its sides and the included angle are given)

       Step 1: Draw QR = 3.6 cm

      Step 2: Draw RS,making angle 45^o with QR.ie QRP = 45^o

      Step 3: From RS,cut RP = 3 cm.

     Step 4: Join Q and P.PQR is the required traingle.

3. Construct an isosceles traingle ABC when base BC = 6.8 cm and A = 90^o.

             Since ABC is isosceles and A = 90^o,B = C = 45^o,since base angles are equal.

                  Step 1: Draw BC = 6.8 cm

                  Step 2: Since base angles are equal,B = C = 45^o,Draw BP making PBC = 45^o

                  Step 3: Draw CQ making BCQ = 45^o

                  Step 4: BP and CQ meeting at A,ABC is the required triangle.

4. Construct an equilateral triangle ABC in which AB = 6 cm.

                  Each angle of an equilateral traingle is 60^o.

                  Step 1: Draw a line AB = 6 cm

                  Step 2: With A as centre draw AP with PAB = 60^o

                 Step 3: With B as centre draw BQ with ABQ = 60^o

                 Step 4: AP and BQ intersect at C.

                ABC is the required triangle