Question

The sides of a triangle are in the ratio 3 :5 : 7. If the perimeter of the triangle is 30 cm, find the sides of the triangle.

Answer 1

Huiiii

Your answer is

15√3 sq cm...

perimeter(p)=30 cm

let the sides be 3x ,5x,7x (because the ratio is given)

perimeter is sum of all sides

thus... 3x+5x+7x =30

15x=30

x=2

therefore the sides are as follows

a=3x=6

b=5x=10

c=7x=14

the area can be found using herons formula which will be as follows

s=a+b+c/2

s=15

area=√s(s-a) (s-b) (s-c)

=√15 *9*5*1

=√5 *3*3*3*5

=15√3 sq cm

Hope it will help you

Answer 2

Answer :

The sides of the triangle are 6 cm, 10 cm and 14 cm.

Given :

• The sides of a triangle are in the ratio 3:5:7.
• The perimeter of the triangle is 30 cm.

To find :

• Sides of the triangle.

Solution :

Consider ,

• 1st side = 3x cm
• 2nd side = 5x cm
• 3rd side = 7x cm

Formula Used :-

${\boxed{\sf{Perimeter\:of\: triangle=a+b+c}}}$

According to the question :-

$\to\sf{3x+5x+7x=30}$

$\to\sf{15x=30}$

$\to\sf{x=\dfrac{30}{15}}$

$\to\sf{x=2}$

• 1st side = 3×2 = 6 cm
• 2nd side = 5×2 = 10 cm
• 3rd side = 7×2 = 14 cm

_________________

★ Verification ★

• 1st side = 6 cm
• 2nd side = 10 cm
• 3rd side = 14 cm

Perimeter of triangle = 30

→ 6+10+14 = 30

→ 30 = 30

Hence Verified !!