Question

find the area of the triangle whose perimeter is 180 cm and two of its sides are of lenght 80 cm nd 18 cm

Answer 1

Question:

find the area of the triangle whose perimeter is 180 cm and two of its sides are of length 80 cm and 18 cm

To find:

The area of the triangle

Given:

• Perimeter of the triangle=180cm
• Two of the sides mesures=80cm,18cm

So,

    The 3rd side of the triangle={180-(80+18)}cm

                                                    ={180-98}cm

                                                    =82cm

Check:

         The three sides of the triangle=82cm,80cm and 18cm

Thus,

      The no sides of the triangle is equal then the triangle is a scalene triangle.

The "S" of scalene triangle=$\frac{Perimeter of the triangle}{2}$

[Note here,side 82cm be a , side 80cm be b , side 18cm be c}

Area of scalene triangle=$\sqrt{s(s-a)(s-b)(s-c)}$    

Solution:

The "s" of the triangle=$\frac{180}{2}$=90

The area of the triangle=$\sqrt{90(90-82)(90-80)(90-18)}$  $cm^{2}$

                                      =$\sqrt{90 * 8 * 10 * 72}$  $cm^{2}$

                                      =$\sqrt{518400}$  $cm^{2}$

                                      =$\sqrt{720 * 720}$  $cm^{2}$

                                      =720$cm^{2}$

Answer:

The area of the triangle=720$cm^{2}$