Question

1. The length of the sides of a triangle are in the ratio
3:4:5 and its perimeter is 144 cm. The area of the
triangle is
(a) 684 cm
(b) 664 cm
(c) 764 cm
(d) 864 cm​

Answer 1

Answer:

28.8cm

Step-by-step explanation:

Let the sides of triangles are 3x,4x and 5x.

And perimeter of the triangle is 144cm.

So , 3x+4x+5x=144

        12x=144

          x=12

so, the sides are triangle are 3(12)=36cm, 4(12)=48cm , 5(12)=60cm

so , the longest side is 60 cm.

Area of triangle =s(s−a)(s−b)(s−c)

here , s=72 and a=36, b=48 c=60

                           = 72(72−36)(72−48)(72−60)

                            = 72(36)(24)(12)

                             = 746496

                              = 864

So, the area of triangle is 864 cm2 and the height corresponding to longest side h=602×864=28.8cm

Answer 2

Answer:

option d. 864 cm² is the correct answer.