Math, asked by RajTaringani5, 10 months ago

Find the area of a triangle two sides of which are 18 cm and 10 cm and the perimeter is 42cm.?

Answers

Answered by Anonymous
2

Answer:

Solution:

Assume the third side of the triangle to be “x”.

Now, the three sides of the triangle are 18 cm, 10 cm, and “x” cm

It is given that the perimeter of the triangle = 42cm

So, x = 42 – (18 + 10) cm = 14 cm

∴ The semi perimeter of triangle = 42/2 = 21 cm

Using Heron’s formula,

Area of the triangle,

= √[s (s-a) (s-b) (s-c)]

= √[21(21 – 18) (21 – 10) (21 – 14)] cm2

= √[21 × 3 × 11 × 7] m2

= 21√11 cm2

Hope it will be helpful :)

Answered by avitaylor101
22

Step-by-step explanation:

perimeter of triangle = 42 cm

let, 3rd side be x then,

x + 18 cm + 10 cm = 42 cm

x =( 42 - 28 ) cm

x = 14 cm

Now,

according to formula = s( s - a ) (s - b) ( s - c)

so,

s =( 14 + 28 + 10) / 2 = 21

Than, putting ón formula

21 ( 21 -18 ) ( 21 - 10 ) ( 21 - 14 )

= 21 x 3 x 11 x 7

= 4851

= 69.64 cm² answer

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