Question
Find the area of a triangle two sides of which are 18 cm and 10 cm and the perimeter is 42 cm.
Solution
a = 18 cm
b = 10 cm Perimeter - 42 cm
⇒ a + b + c = 42
⇒ 18 + 10 + c = 42
⇒ 28 + c = 42
⇒ c = 42 – 28
⇒ c = 14 cm
Area of the triangle
