Find the area of triangle whose sides are 10 cm, 12 cm, and 18 cm.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 40 √2 cm2
Given that
The sides of a triangle are 10, 12, and 18 cm
Formula used
The area of triangle ABC = √[s × (s – a) × (s – b) × (s – c)]
where, a, b, and c are the sides of the triangle and s is the semiperimeter of the triangle
Calculation
Semiperimeter (s) = (a + b + c)/2 = (10 + 12 + 18)/2 = 40/2 = 20 cm
The area of the triangle ABC = √[20 × (20 – 10) × (20 – 12) × (20 – 18)]
= √[20 × 10 × 8 × 2] = √3200 = 40 √2 cm2