In triangle PQR, PQ = 6 cm, PR = 8 cm, and QR = 12 cm. Calculate the area of the triangle PQR ?

• In triangle PQR, by using heron’s formula

• S = P + Q + R / 2

• S = 6 + 8 + 12 / 2

• = 26 / 2 = 13

• S = 13

• Area of the triangle PQR = sqrt ( S (S – P) * (S – Q) * (S – R) )

• = sqrt ( 13 (13 – 6) * (13 – 8) * (13 – 12) )

• = sqrt ( 455 )

• Area of the triangle PQR =

21.33 cm²