Question

sides of a traingle are in the ratio 3:4:5 and its perimeter is 12 cm .find its area​

Answer 1

Answer:

perimeter of triangle = 3x+4x+5x

= 12x

=12 cm =12x

=x=1

so sides are 3,4,5.

area of triangle = 1/2 (base *height)

=1/2 (4*5 )

= 1/2*20

= 10

Answer 2

Answer:

Let the sides be 3x,4x,5x

3x+4x+5x=12cm

12x=12cm

x=1cm

Semi-perimeter(s)=12cm/2=6cm

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

$=\sqrt{6(6-3x)(6-4x)(6-5x)}$

=√(6*3*2*1)

=√36

$=6cm^{2}$

Therefore, AREA=6cm2