Question

13. The perimeter of a triangle is 36 cm and its sides are in the ratio 3: 4:5. Find the area of the triangle
III. Solve:
3x3=9​

Answer 1

Answer:

Step-by-step explanation:

Let sides are 3 x , 4 x and 5 x ,

Given that perimeter of the triangle is 36 cm.

So, sum of all sides =36 cm

↪ 3 x + 4 x + 5 x = 3 6

↪ 1 2 x = 3 6

↪ x = 3

So,

Sides are 3 x = 3 × 3 = 9 cm

4 x = 4 × 3 = 12 cm

5 x = 5 × 3 = 15

As we can see that 3 , 4 and 5 are Pythagorean triplets.

Area of triangle = ( 3 x × 4 x ) / 2

Area of triangle = 6 x² cm²

Area of triangle = 6( 3 )³ cm²

Area of triangle = 162 cm²

Answer 2

Answer:

9 : 12 : 15

Step-by-step explanation:

Let the side be x

Therefore

3x + 4× + 5x = 36

12x = 36

x = 36/12

x = 3

Therefore

3x = 3×3

3x = 9

4x = 4×3

4x = 12

5x = 5×3

5x = 15

Hence - 9:12:15