Correct Answer - Option 4 : 864 cm
2
Given:
The length of the sides of a triangle is in the ratio 3 : 4 : 5.
The perimeter of triangle is 144 cm.
Formula Used:
Perimeter = Sum of all sides
Area of right-angled triangle = 1/2 × Base × Height
Calculation:
Let the sides of the triangle be 3x, 4x, 5x.
The perimeter of triangle is 144 cm.
⇒ 3x + 4x + 5x = 144
⇒ 12x = 144
⇒ x = 12 cm
The sides = 3 × 12 = 36, 4 × 12 = 48, 5 × 12 = 60
The length of the sides of a triangle is in the ratio 3 : 4 : 5.
It show that the triangle is right angled triangle
Area of triangle = 1/2 × 36 × 48 = 864 cm2
∴ The area of the triangle is 864 cm2