Question

the perimeter of an angle is 120cm and its sides are in the ratio of the 5:12:13 find the area of the triangles

Answer 1

We are given that the sides are in the ratio 5:12:13.

Let the sides be 5x,12x and 13x.

Perimeter = 120 cm

Therefore, 5x + 12x + 13x = 120

x= 4

∴The sides are

a = 5×4 = 20cm
b = 12×4 = 48cm
c = 13×4 = 52cm



Semi-perimeter is given by

s = 120/2 = 60cm



Using Heron's formula for calculating the area of a triangle,

Area = √s(s - a) (s -b) (s -c)

= √60(60 - 20) (60 - 48) (60 - 52)

= √60 × 40 × 12 × 8

= 480cm^2



Therefore, area of the traingle = 480cm^2

Done, Congrats!❤️

Answer 2

Hmm,

I think you mean about perimeter of triangle interested of angle

so here is your answer

Let the sides of triangle be

=>5x
=>12x
=>13x

Perimeter given is 120cm

=>5x+12x+13x=120
=>30x=120
=>4cm

So the sides are

=>5x= 5x4=20cm

=>12x= 12x4=48cm

=>13x= 13x4=52cm

Let's see that this is right angled triangle or not

Using Pythagoras theorem
5^2+12^2=15^2
25+144=225
169=225

So this is not a right angled triangle

Using Heron's Formula find area of triangle

=>2S=a+b+c
=>2S=20+48+52
=>S=60

Heron's Formula= √S(S-a)(S-b)(S-c)

=>√60(60-20)(60-48)(60-52)

=>480 cm^2