Question

A triangle wall of a garden has been painted from one side. The sides of the wall are 15m,12m,5m
1) write the formula to find the area of the wall.
2)write the formula to find the semi perimeter of the wall? 3)find the semi perimeter of the wall?
4)find the area to of the wall? 5)find the perimeter of the wall? ​

Answer 1

Answer:

see if sides are given the formula is

$s = a + b + c \div 2$

then

√s(s-a)(s-b)(s-c)

Answer 2

(1) Write the formula to find the area of the wall.

$\sf Area \: of \: Triangle = \sqrt{s(s - a) \: (s - b) \: (s - c)}$

Where,

• S = Semi - Perimeter
• A = Side 1
• B = Side 2
• C = Side 3

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(2) Write the formula to find the semi perimeter of the wall ?

$\sf \: \dfrac{a + b + c}{2}$

Where,

• A = Side 1
• B = Side 2
• C = Side 3

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(3) Find the semi perimeter of the wall ?

$\sf \: Semi \: perimeter = \dfrac{a + b + c}{2}$

$\sf \: = \dfrac{15 + 12 + 5}{2}$

$\sf = \dfrac{32}{2}$

$\sf \: = 16 cm$

Hence, the Semi Perimeter of 16 cm.

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(4) Find the area to of the wall ?

$\sf Area \: of \: Triangle = \sqrt{s(s - a) \: (s - b) \: (s - c)}$

$\sf Area = \sqrt{16(16 - 15) \: (16 - 12) \: (16 - 5)}$

$\sf Area = \sqrt{16 \times (1) \times \: (4) \times \: (11)}$

$= \sqrt{704}$

$\sf \: = 26.5 \: cm$

Hence, the Area of the wall is 26.5 cm.

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(5) Find the perimeter of the wall ?

$\sf \: Perimeter \: of \: Triangle = a + b + c$

$\sf = 15 + 16 + 5 \: cm$

$\sf \: \: = 36 \: cm$

Hence, the perimeter of the wall is 36 cm.